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.

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.

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)

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.

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.

ID	Name	Product	Family	Published	Updated	Severity
85928	SUSE SLED12 / SLES12 Security Update : openssh (SUSE-SU-2015:1544-1) (Logjam)	Nessus	SuSE Local Security Checks	9/14/2015	12/5/2022	low
85941	SUSE SLED11 Security Update : openssh (SUSE-SU-2015:1547-2) (Logjam)	Nessus	SuSE Local Security Checks	9/15/2015	12/5/2022	low
86656	AIX OpenSSH Advisory : openssh_advisory6.asc	Nessus	AIX Local Security Checks	10/29/2015	4/21/2023	medium
87128	CentOS 7 : openssh (CESA-2015:2088)	Nessus	CentOS Local Security Checks	12/2/2015	1/4/2021	high
91432	F5 Networks BIG-IP : OpenSSH vulnerabilities (K17263)	Nessus	F5 Networks Local Security Checks	6/2/2016	1/4/2019	medium

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