Use-after-free vulnerability in the mm_answer_pam_free_ctx function in monitor.c in sshd in OpenSSH before 7.0 on non-OpenBSD platforms might allow local users to gain privileges by leveraging control of the sshd uid to send an unexpectedly early MONITOR_REQ_PAM_FREE_CTX request.

The version of Junos OS installed on the remote host is prior to 12.3X48-D55, 12.3R12-S13, 15.1X49-D100, 15.1F6-S12, 16.1R3-S4, 16.2R1-S4, 17.1R1-S2, or 17.2R1. It is, therefore, affected by a vulnerability as referenced in the JSA10940 advisory. Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

According to its self-reported version number, the remote pfSense install is prior to 2.2.5. It is, therefore, affected by multiple vulnerabilities as stated in the referenced vendor advisories.

Security Fix(es) :

  - It was found that the OpenSSH client did not properly     enforce the ForwardX11Timeout setting. A malicious or     compromised remote X application could possibly use this     flaw to establish a trusted connection to the local X     server, even if only untrusted X11 forwarding was     requested. (CVE-2015-5352)

  - A flaw was found in the way OpenSSH handled PAM     authentication when using privilege separation. An     attacker with valid credentials on the system and able     to fully compromise a non-privileged pre-authentication     process using a different flaw could use this flaw to     authenticate as other users. (CVE-2015-6563)

  - A use-after-free flaw was found in OpenSSH. An attacker     able to fully compromise a non-privileged     pre-authentication process using a different flaw could     possibly cause sshd to crash or execute arbitrary code     with root privileges. (CVE-2015-6564)

  - An access flaw was discovered in OpenSSH; the OpenSSH     client did not correctly handle failures to generate     authentication cookies for untrusted X11 forwarding. A     malicious or compromised remote X application could     possibly use this flaw to establish a trusted connection     to the local X server, even if only untrusted X11     forwarding was requested. (CVE-2016-1908)

CVE-2015-6563 The monitor component in sshd in OpenSSH before 7.0 on non-OpenBSD platforms accepts extraneous username data in MONITOR_REQ_PAM_INIT_CTX requests, which allows local users to conduct impersonation attacks by leveraging any SSH login access in conjunction with control of the sshd uid to send a crafted MONITOR_REQ_PWNAM request, related to monitor.c and monitor_wrap.c.

CVE-2015-6564 Use-after-free vulnerability in the mm_answer_pam_free_ctx function in monitor.c in sshd in OpenSSH before 7.0 on non-OpenBSD platforms might allow local users to gain privileges by leveraging control of the sshd uid to send an unexpectedly early MONITOR_REQ_PAM_FREE_CTX request.

An update for openssh is now available for Red Hat Enterprise Linux 6.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

OpenSSH is an SSH protocol implementation supported by a number of Linux, UNIX, and similar operating systems. It includes the core files necessary for both the OpenSSH client and server.

Security Fix(es) :

* It was found that the OpenSSH client did not properly enforce the ForwardX11Timeout setting. A malicious or compromised remote X application could possibly use this flaw to establish a trusted connection to the local X server, even if only untrusted X11 forwarding was requested. (CVE-2015-5352)

* A flaw was found in the way OpenSSH handled PAM authentication when using privilege separation. An attacker with valid credentials on the system and able to fully compromise a non-privileged pre-authentication process using a different flaw could use this flaw to authenticate as other users. (CVE-2015-6563)

* A use-after-free flaw was found in OpenSSH. An attacker able to fully compromise a non-privileged pre-authentication process using a different flaw could possibly cause sshd to crash or execute arbitrary code with root privileges. (CVE-2015-6564)

* An access flaw was discovered in OpenSSH; the OpenSSH client did not correctly handle failures to generate authentication cookies for untrusted X11 forwarding. A malicious or compromised remote X application could possibly use this flaw to establish a trusted connection to the local X server, even if only untrusted X11 forwarding was requested. (CVE-2016-1908)

For detailed information on changes in this release, see the Red Hat Enterprise Linux 6.8 Release Notes and Red Hat Enterprise Linux 6.8 Technical Notes linked from the References section.

From Red Hat Security Advisory 2016:0741 :

An update for openssh is now available for Red Hat Enterprise Linux 6.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

OpenSSH is an SSH protocol implementation supported by a number of Linux, UNIX, and similar operating systems. It includes the core files necessary for both the OpenSSH client and server.

Security Fix(es) :

* It was found that the OpenSSH client did not properly enforce the ForwardX11Timeout setting. A malicious or compromised remote X application could possibly use this flaw to establish a trusted connection to the local X server, even if only untrusted X11 forwarding was requested. (CVE-2015-5352)

* A flaw was found in the way OpenSSH handled PAM authentication when using privilege separation. An attacker with valid credentials on the system and able to fully compromise a non-privileged pre-authentication process using a different flaw could use this flaw to authenticate as other users. (CVE-2015-6563)

* A use-after-free flaw was found in OpenSSH. An attacker able to fully compromise a non-privileged pre-authentication process using a different flaw could possibly cause sshd to crash or execute arbitrary code with root privileges. (CVE-2015-6564)

* An access flaw was discovered in OpenSSH; the OpenSSH client did not correctly handle failures to generate authentication cookies for untrusted X11 forwarding. A malicious or compromised remote X application could possibly use this flaw to establish a trusted connection to the local X server, even if only untrusted X11 forwarding was requested. (CVE-2016-1908)

For detailed information on changes in this release, see the Red Hat Enterprise Linux 6.8 Release Notes and Red Hat Enterprise Linux 6.8 Technical Notes linked from the References section.

The remote Redhat Enterprise Linux 6 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2016:0741 advisory.

  - openssh: XSECURITY restrictions bypass under certain conditions in ssh(1) (CVE-2015-5352)

  - openssh: Privilege separation weakness related to PAM support (CVE-2015-6563)

  - openssh: Use-after-free bug related to PAM support (CVE-2015-6564)

  - openssh: possible fallback from untrusted to trusted X11 forwarding (CVE-2016-1908)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Versions of OpenSSH server before 7.0 are affected by multiple vulnerabilities: 

 - A flaw in the 'kbdint_next_device()' function in 'file auth2-chall.c' that allows the circumvention of MaxAuthTries during keyboard-interactive authentication. An attacker can exploit this issue to force the same authentication method to be tried thousands of times in a single pass by using a crafted keyboard-interactive 'devices' string, thus allowing a brute-force attack or causing a denial of service. (CVE-2015-5600) 
 - A flaw in sshd(8) is due to the program setting insecure world-writable permissions for TTYs allowing a local attacker to execute arbitrary commands for logged-in users by injecting crafted terminal escape sequences. (CVE-2015-6565) 
 - A flaw in the monitor component is triggered when handling username data in MONITOR_REQ_PAM_INIT_CTX requests allowing a local user to leverage the SSH login access and control of the sshd(8) UID to send a MONITOR_REQ_PWNAM request to conduct an impersonation attack. (CVE-2015-6563) 
 - A use-after-free error in the 'mm_answer_pam_free_ctx()' function of monitor.c is triggered when handling a MONITOR_REQ_PAM_FREE_CTX request allowing a local attacker to take control of the sshd UID to send a request leading to a dereference of already freed memory and gain elevated privileges. (CVE-2015-6564)

Note: NNM has solely relied on the banner of the SSH client to perform this check. Any backported patches or workarounds such as recompiling or edited configurations are not observable through the banner.

A flaw was found in the way OpenSSH handled PAM authentication when using privilege separation. An attacker with valid credentials on the system and able to fully compromise a non-privileged pre-authentication process using a different flaw could use this flaw to authenticate as other users. (CVE-2015-6563)

A use-after-free flaw was found in OpenSSH. An attacker able to fully compromise a non-privileged pre-authentication process using a different flaw could possibly cause sshd to crash or execute arbitrary code with root privileges. (CVE-2015-6564)

It was discovered that the OpenSSH sshd daemon did not check the list of keyboard-interactive authentication methods for duplicates. A remote attacker could use this flaw to bypass the MaxAuthTries limit, making it easier to perform password guessing attacks. (CVE-2015-5600)

It was found that the OpenSSH ssh-agent, a program to hold private keys used for public key authentication, was vulnerable to password guessing attacks. An attacker able to connect to the agent could use this flaw to conduct a brute-force attack to unlock keys in the ssh-agent.

This update fixes the following bugs :

  - Previously, the sshd_config(5) man page was misleading     and could thus confuse the user. This update improves     the man page text to clearly describe the AllowGroups     feature.

  - The limit for the function for restricting the number of     files listed using the wildcard character (*) that     prevents the Denial of Service (DoS) for both server and     client was previously set too low. Consequently, the     user reaching the limit was prevented from listing a     directory with a large number of files over Secure File     Transfer Protocol (SFTP). This update increases the     aforementioned limit, thus fixing this bug.

  - When the ForceCommand option with a pseudoterminal was     used and the MaxSession option was set to '2',     multiplexed SSH connections did not work as expected.
    After the user attempted to open a second multiplexed     connection, the attempt failed if the first connection     was still open. This update modifies OpenSSH to issue     only one audit message per session, and the user is thus     able to open two multiplexed connections in this     situation.

  - The ssh-copy-id utility failed if the account on the     remote server did not use an sh-like shell. Remote     commands have been modified to run in an sh-like shell,     and ssh-copy-id now works also with non-sh-like shells.

  - Due to a race condition between auditing messages and     answers when using ControlMaster multiplexing, one     session in the shared connection randomly and     unexpectedly exited the connection. This update fixes     the race condition in the auditing code, and     multiplexing connections now work as expected even with     a number of sessions created at once.

In addition, this update adds the following enhancements :

  - As not all Lightweight Directory Access Protocol (LDAP)     servers possess a default schema, as expected by the     ssh-ldap-helper program, this update provides the user     with an ability to adjust the LDAP query to get public     keys from servers with a different schema, while the     default functionality stays untouched.

  - With this enhancement update, the administrator is able     to set permissions for files uploaded using Secure File     Transfer Protocol (SFTP).

  - This update provides the LDAP schema in LDAP Data     Interchange Format (LDIF) format as a complement to the     old schema previously accepted by OpenLDAP.

  - With this update, the user can selectively disable the     Generic Security Services API (GSSAPI) key exchange     algorithms as any normal key exchange.

The remote host is affected by the vulnerability described in GLSA-201512-04 (OpenSSH: Multiple vulnerabilities)

    Multiple vulnerabilities have been discovered in OpenSSH. Please review       the CVE identifiers referenced below for details.
  Impact :

  Workaround :

    There is no known workaround at this time.

A flaw was found in the way OpenSSH handled PAM authentication when using privilege separation. An attacker with valid credentials on the system and able to fully compromise a non-privileged pre-authentication process using a different flaw could use this flaw to authenticate as other users.

It was discovered that the OpenSSH sshd daemon did not check the list of keyboard-interactive authentication methods for duplicates. A remote attacker could use this flaw to bypass the MaxAuthTries limit, making it easier to perform password guessing attacks.

A use-after-free flaw was found in OpenSSH. An attacker able to fully compromise a non-privileged pre-authentication process using a different flaw could possibly cause sshd to crash or execute arbitrary code with root privileges.

Updated openssh packages that fix multiple security issues, several bugs, and add various enhancements are now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having Moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

OpenSSH is OpenBSD's SSH (Secure Shell) protocol implementation. These packages include the core files necessary for both the OpenSSH client and server.

A flaw was found in the way OpenSSH handled PAM authentication when using privilege separation. An attacker with valid credentials on the system and able to fully compromise a non-privileged pre-authentication process using a different flaw could use this flaw to authenticate as other users. (CVE-2015-6563)

A use-after-free flaw was found in OpenSSH. An attacker able to fully compromise a non-privileged pre-authentication process using a different flaw could possibly cause sshd to crash or execute arbitrary code with root privileges. (CVE-2015-6564)

It was discovered that the OpenSSH sshd daemon did not check the list of keyboard-interactive authentication methods for duplicates. A remote attacker could use this flaw to bypass the MaxAuthTries limit, making it easier to perform password guessing attacks. (CVE-2015-5600)

It was found that the OpenSSH ssh-agent, a program to hold private keys used for public key authentication, was vulnerable to password guessing attacks. An attacker able to connect to the agent could use this flaw to conduct a brute-force attack to unlock keys in the ssh-agent. (BZ#1238238)

This update fixes the following bugs :

* Previously, the sshd_config(5) man page was misleading and could thus confuse the user. This update improves the man page text to clearly describe the AllowGroups feature. (BZ#1150007)

* The limit for the function for restricting the number of files listed using the wildcard character (*) that prevents the Denial of Service (DoS) for both server and client was previously set too low.
Consequently, the user reaching the limit was prevented from listing a directory with a large number of files over Secure File Transfer Protocol (SFTP). This update increases the aforementioned limit, thus fixing this bug. (BZ#1160377)

* When the ForceCommand option with a pseudoterminal was used and the MaxSession option was set to '2', multiplexed SSH connections did not work as expected. After the user attempted to open a second multiplexed connection, the attempt failed if the first connection was still open. This update modifies OpenSSH to issue only one audit message per session, and the user is thus able to open two multiplexed connections in this situation. (BZ#1199112)

* The ssh-copy-id utility failed if the account on the remote server did not use an sh-like shell. Remote commands have been modified to run in an sh-like shell, and ssh-copy-id now works also with non-sh-like shells. (BZ#1201758)

* Due to a race condition between auditing messages and answers when using ControlMaster multiplexing, one session in the shared connection randomly and unexpectedly exited the connection. This update fixes the race condition in the auditing code, and multiplexing connections now work as expected even with a number of sessions created at once.
(BZ#1240613)

In addition, this update adds the following enhancements :

* As not all Lightweight Directory Access Protocol (LDAP) servers possess a default schema, as expected by the ssh-ldap-helper program, this update provides the user with an ability to adjust the LDAP query to get public keys from servers with a different schema, while the default functionality stays untouched. (BZ#1201753)

* With this enhancement update, the administrator is able to set permissions for files uploaded using Secure File Transfer Protocol (SFTP). (BZ#1197989)

* This update provides the LDAP schema in LDAP Data Interchange Format (LDIF) format as a complement to the old schema previously accepted by OpenLDAP. (BZ#1184938)

* With this update, the user can selectively disable the Generic Security Services API (GSSAPI) key exchange algorithms as any normal key exchange. (BZ#1253062)

Users of openssh are advised to upgrade to these updated packages, which correct these issues and add these enhancements.

From Red Hat Security Advisory 2015:2088 :

Updated openssh packages that fix multiple security issues, several bugs, and add various enhancements are now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having Moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

OpenSSH is OpenBSD's SSH (Secure Shell) protocol implementation. These packages include the core files necessary for both the OpenSSH client and server.

A flaw was found in the way OpenSSH handled PAM authentication when using privilege separation. An attacker with valid credentials on the system and able to fully compromise a non-privileged pre-authentication process using a different flaw could use this flaw to authenticate as other users. (CVE-2015-6563)

A use-after-free flaw was found in OpenSSH. An attacker able to fully compromise a non-privileged pre-authentication process using a different flaw could possibly cause sshd to crash or execute arbitrary code with root privileges. (CVE-2015-6564)

It was discovered that the OpenSSH sshd daemon did not check the list of keyboard-interactive authentication methods for duplicates. A remote attacker could use this flaw to bypass the MaxAuthTries limit, making it easier to perform password guessing attacks. (CVE-2015-5600)

It was found that the OpenSSH ssh-agent, a program to hold private keys used for public key authentication, was vulnerable to password guessing attacks. An attacker able to connect to the agent could use this flaw to conduct a brute-force attack to unlock keys in the ssh-agent. (BZ#1238238)

This update fixes the following bugs :

* Previously, the sshd_config(5) man page was misleading and could thus confuse the user. This update improves the man page text to clearly describe the AllowGroups feature. (BZ#1150007)

* The limit for the function for restricting the number of files listed using the wildcard character (*) that prevents the Denial of Service (DoS) for both server and client was previously set too low.
Consequently, the user reaching the limit was prevented from listing a directory with a large number of files over Secure File Transfer Protocol (SFTP). This update increases the aforementioned limit, thus fixing this bug. (BZ#1160377)

* When the ForceCommand option with a pseudoterminal was used and the MaxSession option was set to '2', multiplexed SSH connections did not work as expected. After the user attempted to open a second multiplexed connection, the attempt failed if the first connection was still open. This update modifies OpenSSH to issue only one audit message per session, and the user is thus able to open two multiplexed connections in this situation. (BZ#1199112)

* The ssh-copy-id utility failed if the account on the remote server did not use an sh-like shell. Remote commands have been modified to run in an sh-like shell, and ssh-copy-id now works also with non-sh-like shells. (BZ#1201758)

* Due to a race condition between auditing messages and answers when using ControlMaster multiplexing, one session in the shared connection randomly and unexpectedly exited the connection. This update fixes the race condition in the auditing code, and multiplexing connections now work as expected even with a number of sessions created at once.
(BZ#1240613)

In addition, this update adds the following enhancements :

* As not all Lightweight Directory Access Protocol (LDAP) servers possess a default schema, as expected by the ssh-ldap-helper program, this update provides the user with an ability to adjust the LDAP query to get public keys from servers with a different schema, while the default functionality stays untouched. (BZ#1201753)

* With this enhancement update, the administrator is able to set permissions for files uploaded using Secure File Transfer Protocol (SFTP). (BZ#1197989)

* This update provides the LDAP schema in LDAP Data Interchange Format (LDIF) format as a complement to the old schema previously accepted by OpenLDAP. (BZ#1184938)

* With this update, the user can selectively disable the Generic Security Services API (GSSAPI) key exchange algorithms as any normal key exchange. (BZ#1253062)

Users of openssh are advised to upgrade to these updated packages, which correct these issues and add these enhancements.

The remote AIX host has a version of OpenSSH installed that is affected by the following vulnerabilities :

  - A flaw exists in the monitor component when handling     extraneous username data in MONITOR_REQ_PAM_INIT_CTX     requests. A local attacker can exploit this issue to     conduct an impersonation attack, by sending a crafted     MONITOR_REQ_PWNAM request that leverages any SSH login     access with control of the sshd UID. (CVE-2015-6563)

  - A use-after-free error exists in function     mm_answer_pam_free_ctx() in the file monitor.c when     handling MONITOR_REQ_PAM_FREE_CTX requests. A local     attacker can exploit this to gain elevated privileges,     by leveraging control of the sshd UID to send an     unexpectedly early MONITOR_REQ_PAM_FREE_CTX request.
    (CVE-2015-6564)

OpenSSH was updated to fix several security issues and bugs.

Please note that due to a bug in the previous shipped openssh version, sshd might not correctly restart. Please verify that the ssh daemon is running after installing this update.

These security issues were fixed :

  - CVE-2015-5352: The x11_open_helper function, when     ForwardX11Trusted mode is not used, lacked a check of     the refusal deadline for X connections, which made it     easier for remote attackers to bypass intended access     restrictions via a connection outside of the permitted     time window. (bsc#936695)

  - CVE-2015-5600: The kbdint_next_device function in     auth2-chall.c in sshd did not properly restrict the     processing of keyboard-interactive devices within a     single connection, which made it easier for remote     attackers to conduct brute-force attacks or cause a     denial of service (CPU consumption) via a long and     duplicative list in the ssh

    -oKbdInteractiveDevices option, as demonstrated by a     modified client that provides a different password for     each pam element on this list. (bsc#938746)

  - CVE-2015-4000: Removed and disabled weak DH groups to     address LOGJAM. (bsc#932483)

  - Hardening patch to fix sftp RCE. (bsc#903649)

  - CVE-2015-6563: The monitor component in sshd accepted     extraneous username data in MONITOR_REQ_PAM_INIT_CTX     requests, which allowed local users to conduct     impersonation attacks by leveraging any SSH login access     in conjunction with control of the sshd uid to send a     crafted MONITOR_REQ_PWNAM request, related to monitor.c     and monitor_wrap.c.

  - CVE-2015-6564: Use-after-free vulnerability in the     mm_answer_pam_free_ctx function in monitor.c in sshd     might have allowed local users to gain privileges by     leveraging control of the sshd uid to send an     unexpectedly early MONITOR_REQ_PAM_FREE_CTX request.

Additional a bug was fixed that could lead to openssh not working in chroot (bsc#947458).

Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

openssh was updated to fix several security issues and bugs.

These security issues were fixed :

  - CVE-2015-5352: The x11_open_helper function in     channels.c in ssh in OpenSSH when ForwardX11Trusted mode     is not used, lacked a check of the refusal deadline for     X connections, which made it easier for remote attackers     to bypass intended access restrictions via a connection     outside of the permitted time window (bsc#936695).

  - CVE-2015-5600: The kbdint_next_device function in     auth2-chall.c in sshd in OpenSSH did not properly     restrict the processing of keyboard-interactive devices     within a single connection, which made it easier for     remote attackers to conduct brute-force attacks or cause     a denial of service (CPU consumption) via a long and     duplicative list in the ssh -oKbdInteractiveDevices     option, as demonstrated by a modified client that     provides a different password for each pam element on     this list (bsc#938746).

  - CVE-2015-4000: Removed and disabled weak DH groups to     address LOGJAM (bsc#932483).

  - Hardening patch to fix sftp RCE (bsc#903649).

  - CVE-2015-6563: The monitor component in sshd in OpenSSH     accepted extraneous username data in     MONITOR_REQ_PAM_INIT_CTX requests, which allowed local     users to conduct impersonation attacks by leveraging any     SSH login access in conjunction with control of the sshd     uid to send a crafted MONITOR_REQ_PWNAM request, related     to monitor.c and monitor_wrap.c.

  - CVE-2015-6564: Use-after-free vulnerability in the     mm_answer_pam_free_ctx function in monitor.c in sshd in     OpenSSH might have allowed local users to gain     privileges by leveraging control of the sshd uid to send     an unexpectedly early MONITOR_REQ_PAM_FREE_CTX request.

The update package also includes non-security fixes. See advisory for details.

Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

openssh was updated to fix several security issues.

These security issues were fixed :

  - CVE-2015-5352: The x11_open_helper function in     channels.c in ssh in OpenSSH when ForwardX11Trusted mode     is not used, lacked a check of the refusal deadline for     X connections, which made it easier for remote attackers     to bypass intended access restrictions via a connection     outside of the permitted time window (bsc#936695).

  - CVE-2015-5600: The kbdint_next_device function in     auth2-chall.c in sshd in OpenSSH did not properly     restrict the processing of keyboard-interactive devices     within a single connection, which made it easier for     remote attackers to conduct brute-force attacks or cause     a denial of service (CPU consumption) via a long and     duplicative list in the ssh -oKbdInteractiveDevices     option, as demonstrated by a modified client that     provides a different password for each pam element on     this list (bsc#938746).

  - CVE-2015-4000: Removed and disabled weak DH groups to     address LOGJAM (bsc#932483).

  - Hardening patch to fix sftp RCE (bsc#903649).

  - CVE-2015-6563: The monitor component in sshd in OpenSSH     accepted extraneous username data in     MONITOR_REQ_PAM_INIT_CTX requests, which allowed local     users to conduct impersonation attacks by leveraging any     SSH login access in conjunction with control of the sshd     uid to send a crafted MONITOR_REQ_PWNAM request, related     to monitor.c and monitor_wrap.c. (bsc#943010)

  - CVE-2015-6564: Use-after-free vulnerability in the     mm_answer_pam_free_ctx function in monitor.c in sshd in     OpenSSH might have allowed local users to gain     privileges by leveraging control of the sshd uid to send     an unexpectedly early MONITOR_REQ_PAM_FREE_CTX request.
    (bsc#943006)

Also use %restart_on_update in the trigger script.

Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The monitor component in sshd in OpenSSH before 7.0 on non-OpenBSD platforms accepts extraneous username data in MONITOR_REQ_PAM_INIT_CTX requests, which allows local users to conduct impersonation attacks by leveraging any SSH login access in conjunction with control of the sshd uid to send a crafted MONITOR_REQ_PWNAM request, related to monitor.c and monitor_wrap.c. (CVE-2015-6563)

Use-after-free vulnerability in the mm_answer_pam_free_ctx function in monitor.c in sshd in OpenSSH before 7.0 on non-OpenBSD platforms might allow local users to gain privileges by leveraging control of the sshd uid to send an unexpectedly early MONITOR_REQ_PAM_FREE_CTX request.
(CVE-2015-6564)

This update provides fixes for vulnerabilities published with openssh-7.0 Security fix for CVE-2015-5600

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

OpenSSH 6.8 and 6.9 incorrectly set TTYs to be world-writable. Local attackers may be able to write arbitrary messages to logged-in users, including terminal escape sequences. Reported by Nikolay Edigaryev.

Fixed a privilege separation weakness related to PAM support.
Attackers who could successfully compromise the pre-authentication process for remote code execution and who had valid credentials on the host could impersonate other users.

Fixed a use-after-free bug related to PAM support that was reachable by attackers who could compromise the pre-authentication process for remote code execution.

According to its banner, the version of OpenSSH running on the remote host is prior to 7.0. It is, therefore, affected by the following vulnerabilities :

  - A security bypass vulnerability exists in the     kbdint_next_device() function in file auth2-chall.c that     allows the circumvention of MaxAuthTries during     keyboard-interactive authentication. A remote attacker     can exploit this issue to force the same authentication     method to be tried thousands of times in a single pass     by using a crafted keyboard-interactive 'devices'     string, thus allowing a brute-force attack or causing a     denial of service. (CVE-2015-5600)

  - A security bypass vulnerability exists in sshd due to     improper handling of username data in     MONITOR_REQ_PAM_INIT_CTX requests. A local attacker can     exploit this, by sending a MONITOR_REQ_PWNAM request, to     conduct an impersonation attack. Note that this issue     only affects Portable OpenSSH. (CVE-2015-6563)

  - A privilege escalation vulnerability exists due to a     use-after-free error in sshd that is triggered when     handling a MONITOR_REQ_PAM_FREE_CTX request. A local     attacker can exploit this to gain elevated privileges.
    Note that this issue only affects Portable OpenSSH.
    (CVE-2015-6564)

  - A local command execution vulnerability exists in sshd     due to setting insecure world-writable permissions for     TTYs. A local attacker can exploit this, by injecting     crafted terminal escape sequences, to execute commands     for logged-in users. (CVE-2015-6565)

ID	Name	Product	Family	Severity
130514	Juniper JSA10940	Nessus	Junos Local Security Checks	high
106497	pfSense < 2.2.5 Multiple Vulnerabilities (SA-15_08)	Nessus	Firewalls	high
91540	Scientific Linux Security Update : openssh on SL6.x i386/x86_64 (20160510)	Nessus	Scientific Linux Local Security Checks	critical
91432	F5 Networks BIG-IP : OpenSSH vulnerabilities (K17263)	Nessus	F5 Networks Local Security Checks	medium
91166	CentOS 6 : openssh (CESA-2016:0741)	Nessus	CentOS Local Security Checks	critical
91148	Oracle Linux 6 : openssh (ELSA-2016-0741)	Nessus	Oracle Linux Local Security Checks	critical
91073	RHEL 6 : openssh (RHSA-2016:0741)	Nessus	Red Hat Local Security Checks	critical
9309	OpenSSH < 7.0 Multiple Vulnerabilities	Nessus Network Monitor	SSH	high
87567	Scientific Linux Security Update : openssh on SL7.x x86_64 (20151119)	Nessus	Scientific Linux Local Security Checks	high
87545	GLSA-201512-04 : OpenSSH: Multiple vulnerabilities	Nessus	Gentoo Local Security Checks	high
87351	Amazon Linux AMI : openssh (ALAS-2015-625)	Nessus	Amazon Linux Local Security Checks	high
87128	CentOS 7 : openssh (CESA-2015:2088)	Nessus	CentOS Local Security Checks	high
87019	Oracle Linux 7 : openssh (ELSA-2015-2088)	Nessus	Oracle Linux Local Security Checks	high
86967	RHEL 7 : openssh (RHSA-2015:2088)	Nessus	Red Hat Local Security Checks	high
86656	AIX OpenSSH Advisory : openssh_advisory6.asc	Nessus	AIX Local Security Checks	medium
86339	SUSE SLED11 / SLES11 Security Update : openssh (SUSE-SU-2015:1695-1) (Logjam)	Nessus	SuSE Local Security Checks	low
86057	SUSE SLED11 / SLES11 Security Update : openssh (SUSE-SU-2015:1581-1) (Logjam)	Nessus	SuSE Local Security Checks	low
85941	SUSE SLED11 Security Update : openssh (SUSE-SU-2015:1547-2) (Logjam)	Nessus	SuSE Local Security Checks	low
85929	SUSE SLES11 Security Update : openssh (SUSE-SU-2015:1547-1) (Logjam)	Nessus	SuSE Local Security Checks	low
85928	SUSE SLED12 / SLES12 Security Update : openssh (SUSE-SU-2015:1544-1) (Logjam)	Nessus	SuSE Local Security Checks	low
85750	Amazon Linux AMI : openssh (ALAS-2015-592)	Nessus	Amazon Linux Local Security Checks	medium
85668	Fedora 21 : openssh-6.6.1p1-16.fc21 (2015-13469)	Nessus	Fedora Local Security Checks	high
85594	FreeBSD : OpenSSH -- PAM vulnerabilities (2920c449-4850-11e5-825f-c80aa9043978)	Nessus	FreeBSD Local Security Checks	high
85382	OpenSSH < 7.0 Multiple Vulnerabilities	Nessus	Misc.	medium

Detections

Analytics

CVE-2015-6564

high

Tenable Plugins

high

high

critical

medium

critical

critical

critical

high

high

high

high

high

high

high

medium

low

low

low

low

low

medium

high

high

medium