Error handling in the SSH protocol in (1) SSH Tectia Client and Server and Connector 4.0 through 4.4.11, 5.0 through 5.2.4, and 5.3 through 5.3.8; Client and Server and ConnectSecure 6.0 through 6.0.4; Server for Linux on IBM System z 6.0.4; Server for IBM z/OS 5.5.1 and earlier, 6.0.0, and 6.0.1; and Client 4.0-J through 4.3.3-J and 4.0-K through 4.3.10-K; and (2) OpenSSH 4.7p1 and possibly other versions, when using a block cipher algorithm in Cipher Block Chaining (CBC) mode, makes it easier for remote attackers to recover certain plaintext data from an arbitrary block of ciphertext in an SSH session via unknown vectors.

The version of AHV installed on the remote host is prior to 20230302.102005. It is, therefore, affected by multiple vulnerabilities as referenced in the NXSA-AHV-20230302.100173 advisory.

  - A crafted NTFS image can trigger a heap-based buffer overflow, caused by an unsanitized attribute in     ntfs_get_attribute_value, in NTFS-3G < 2021.8.22. (CVE-2021-39263)

  - EDK2's Network Package is susceptible to a buffer overflow vulnerability when processing DNS Servers     option from a DHCPv6 Advertise message. This vulnerability can be exploited by an attacker to gain     unauthorized access and potentially lead to a loss of Confidentiality, Integrity and/or Availability.
    (CVE-2023-45234)

  - A NULL pointer dereference was found In libssh during re-keying with algorithm guessing. This issue may     allow an authenticated client to cause a denial of service. (CVE-2023-1667)

  - A vulnerability was found in libssh, where the authentication check of the connecting client can be     bypassed in the`pki_verify_data_signature` function in memory allocation problems. This issue may happen     if there is insufficient memory or the memory usage is limited. The problem is caused by the return value     `rc,` which is initialized to SSH_ERROR and later rewritten to save the return value of the function call     `pki_key_check_hash_compatible.` The value of the variable is not changed between this point and the     cryptographic verification. Therefore any error between them calls `goto error` returning SSH_OK.
    (CVE-2023-2283)

  - A vulnerability was found that the response times to malformed ciphertexts in RSA-PSK ClientKeyExchange     differ from response times of ciphertexts with correct PKCS#1 v1.5 padding. (CVE-2023-5981)

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

The version of AOS installed on the remote host is prior to 6.8. It is, therefore, affected by multiple vulnerabilities as referenced in the NXSA-AOS-6.8 advisory.

  - In spring security versions prior to 5.4.11+, 5.5.7+ , 5.6.4+ and older unsupported versions,     RegexRequestMatcher can easily be misconfigured to be bypassed on some servlet containers. Applications     using RegexRequestMatcher with `.` in the regular expression are possibly vulnerable to an authorization     bypass. (CVE-2022-22978)

  - Error handling in the SSH protocol in (1) SSH Tectia Client and Server and Connector 4.0 through 4.4.11,     5.0 through 5.2.4, and 5.3 through 5.3.8; Client and Server and ConnectSecure 6.0 through 6.0.4; Server     for Linux on IBM System z 6.0.4; Server for IBM z/OS 5.5.1 and earlier, 6.0.0, and 6.0.1; and Client 4.0-J     through 4.3.3-J and 4.0-K through 4.3.10-K; and (2) OpenSSH 4.7p1 and possibly other versions, when using     a block cipher algorithm in Cipher Block Chaining (CBC) mode, makes it easier for remote attackers to     recover certain plaintext data from an arbitrary block of ciphertext in an SSH session via unknown     vectors. (CVE-2008-5161)

  - n Spring Framework versions 5.3.0 - 5.3.16 and older unsupported versions, it is possible for a user to     provide a specially crafted SpEL expression that may cause a denial of service condition. (CVE-2022-22950)

  - VMware Tools contains a SAML token signature bypass vulnerability. A malicious actor that has been granted     Guest Operation Privileges https://docs.vmware.com/en/VMware-vSphere/8.0/vsphere-     security/GUID-6A952214-0E5E-4CCF-9D2A-90948FF643EC.html in a target virtual machine may be able to elevate     their privileges if that target virtual machine has been assigned a more privileged Guest Alias     https://vdc-download.vmware.com/vmwb-repository/dcr-public/d1902b0e-d479-46bf-8ac9-cee0e31e8ec0/07ce8dbd-     db48-4261-9b8f-c6d3ad8ba472/vim.vm.guest.AliasManager.html . (CVE-2023-34058)

  - open-vm-tools contains a file descriptor hijack vulnerability in the vmware-user-suid-wrapper. A malicious     actor with non-root privileges may be able to hijack the /dev/uinput file descriptor allowing them to     simulate user inputs. (CVE-2023-34059)

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

The version of AHV installed on the remote host is prior to 20230302.102005. It is, therefore, affected by multiple vulnerabilities as referenced in the NXSA-AHV-20230302.1011 advisory.

  - Error handling in the SSH protocol in (1) SSH Tectia Client and Server and Connector 4.0 through 4.4.11,     5.0 through 5.2.4, and 5.3 through 5.3.8; Client and Server and ConnectSecure 6.0 through 6.0.4; Server     for Linux on IBM System z 6.0.4; Server for IBM z/OS 5.5.1 and earlier, 6.0.0, and 6.0.1; and Client 4.0-J     through 4.3.3-J and 4.0-K through 4.3.10-K; and (2) OpenSSH 4.7p1 and possibly other versions, when using     a block cipher algorithm in Cipher Block Chaining (CBC) mode, makes it easier for remote attackers to     recover certain plaintext data from an arbitrary block of ciphertext in an SSH session via unknown     vectors. (CVE-2008-5161)

  - The PKCS#11 feature in ssh-agent in OpenSSH before 9.3p2 has an insufficiently trustworthy search path,     leading to remote code execution if an agent is forwarded to an attacker-controlled system. (Code in     /usr/lib is not necessarily safe for loading into ssh-agent.) NOTE: this issue exists because of an     incomplete fix for CVE-2016-10009. (CVE-2023-38408)

  - A NULL pointer dereference was found In libssh during re-keying with algorithm guessing. This issue may     allow an authenticated client to cause a denial of service. (CVE-2023-1667)

  - A vulnerability was found in libssh, where the authentication check of the connecting client can be     bypassed in the`pki_verify_data_signature` function in memory allocation problems. This issue may happen     if there is insufficient memory or the memory usage is limited. The problem is caused by the return value     `rc,` which is initialized to SSH_ERROR and later rewritten to save the return value of the function call     `pki_key_check_hash_compatible.` The value of the variable is not changed between this point and the     cryptographic verification. Therefore any error between them calls `goto error` returning SSH_OK.
    (CVE-2023-2283)

  - Every `named` instance configured to run as a recursive resolver maintains a cache database holding the     responses to the queries it has recently sent to authoritative servers. The size limit for that cache     database can be configured using the `max-cache-size` statement in the configuration file; it defaults to     90% of the total amount of memory available on the host. When the size of the cache reaches 7/8 of the     configured limit, a cache-cleaning algorithm starts to remove expired and/or least-recently used RRsets     from the cache, to keep memory use below the configured limit. It has been discovered that the     effectiveness of the cache-cleaning algorithm used in `named` can be severely diminished by querying the     resolver for specific RRsets in a certain order, effectively allowing the configured `max-cache-size`     limit to be significantly exceeded. This issue affects BIND 9 versions 9.11.0 through 9.16.41, 9.18.0     through 9.18.15, 9.19.0 through 9.19.13, 9.11.3-S1 through 9.16.41-S1, and 9.18.11-S1 through 9.18.15-S1.
    (CVE-2023-2828)

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

The remote Oracle Linux 5 host has packages installed that are affected by a vulnerability as referenced in the ELSA-2009-1287 advisory.

    - workaround to plaintext recovery attack against CBC ciphers CVE-2008-5161 (#502230)

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

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

The version of AHV installed on the remote host is prior to 20230302.102005. It is, therefore, affected by multiple vulnerabilities as referenced in the NXSA-AHV-20230302.207 advisory.

  - In Expat (aka libexpat) before 2.4.3, a left shift by 29 (or more) places in the storeAtts function in     xmlparse.c can lead to realloc misbehavior (e.g., allocating too few bytes, or only freeing memory).
    (CVE-2021-45960)

  - The PKCS#11 feature in ssh-agent in OpenSSH before 9.3p2 has an insufficiently trustworthy search path,     leading to remote code execution if an agent is forwarded to an attacker-controlled system. (Code in     /usr/lib is not necessarily safe for loading into ssh-agent.) NOTE: this issue exists because of an     incomplete fix for CVE-2016-10009. (CVE-2023-38408)

  - An arbitrary file write vulnerability was found in GNU gzip's zgrep utility. When zgrep is applied on the     attacker's chosen file name (for example, a crafted file name), this can overwrite an attacker's content     to an arbitrary attacker-selected file. This flaw occurs due to insufficient validation when processing     filenames with two or more newlines where selected content and the target file names are embedded in     crafted multi-line file names. This flaw allows a remote, low privileged attacker to force zgrep to write     arbitrary files on the system. (CVE-2022-1271)

  - http.client in Python 3.x before 3.5.10, 3.6.x before 3.6.12, 3.7.x before 3.7.9, and 3.8.x before 3.8.5     allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR     and LF control characters in the first argument of HTTPConnection.request. (CVE-2020-26116)

  - urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as     demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this     is similar to CVE-2020-26116. (CVE-2020-26137)

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

Error handling in the SSH protocol in (1) SSH Tectia Client and Server and Connector 4.0 through 4.4.11, 5.0 through 5.2.4, and 5.3 through 5.3.8; Client and Server and ConnectSecure 6.0 through 6.0.4; Server for Linux on IBM System z 6.0.4; Server for IBM z/OS 5.5.1 and earlier, 6.0.0, and 6.0.1; and Client 4.0-J through 4.3.3-J and 4.0-K through 4.3.10-K; and (2) OpenSSH 4.7p1 and possibly other versions, when using a block cipher algorithm in Cipher Block Chaining (CBC) mode, makes it easier for remote attackers to recover certain plaintext data from an arbitrary block of ciphertext in an SSH session by way of unknown vectors. (CVE-2008-5161)

The remote host is affected by the vulnerability described in GLSA-201405-06 (OpenSSH: Multiple vulnerabilities)

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

    A remote attacker could execute arbitrary code, cause a Denial of       Service condition, obtain sensitive information, or bypass environment       restrictions.
  Workaround :

    There is no known workaround at this time.

The version of OpenSSH running on the remote host is affected by the following vulnerabilities :

  - X11 man-in-the-middle attack:
    When attempting to bind(2) to a port that has previously     been bound with SO_REUSEADDR set, most operating systems     check that either the effective user-id matches the     previous bind (common on BSD-derived systems) or that     the bind addresses do not overlap. When the     sshd_config(5) option X11UseLocalhost has been set to     'no' - an attacker may establish a more-specific bind,     which will be used in preference to sshd's wildcard     listener. (CVE-2008-3259)

  - Plaintext Recovery Attack Against SSH:
    If exploited, this attack can potentially allow an     attacker to recover up to 32 bits of plaintext from an     arbitrary block of ciphertext from a connection secured     using the SSH protocol in the standard configuration.
    If OpenSSH is used in the standard configuration, then     the attacker's success probability for recovering 32     bits of plaintext is 2^{-18}. A variant of the attack     against OpenSSH in the standard configuration can     verifiably recover 14 bits of plaintext with probability     2^{-14}. The success probability of the attack for other     implementations of SSH is not known. (CVE-2008-5161)

The SSH server is configured to support Cipher Block Chaining (CBC) encryption.  This may allow an attacker to recover the plaintext message from the ciphertext. 

Note that this plugin only checks for the options of the SSH server and does not check for vulnerable software versions.

CVE-2008-5161 OpenSSH: Plaintext Recovery Attack against CBC ciphers

A flaw was found in the SSH protocol. An attacker able to perform a man-in-the-middle attack may be able to obtain a portion of plain text from an arbitrary ciphertext block when a CBC mode cipher was used to encrypt SSH communication. This update helps mitigate this attack:
OpenSSH clients and servers now prefer CTR mode ciphers to CBC mode, and the OpenSSH server now reads SSH packets up to their full possible length when corruption is detected, rather than reporting errors early, reducing the possibility of successful plain text recovery.
(CVE-2008-5161)

This update also fixes the following bug :

  - the ssh client hung when trying to close a session in     which a background process still held tty file     descriptors open. With this update, this so-called 'hang     on exit' error no longer occurs and the ssh client     closes the session immediately. (BZ#454812)

In addition, this update adds the following enhancements :

  - the SFTP server can now chroot users to various     directories, including a user's home directory, after     log in. A new configuration option -- ChrootDirectory --     has been added to '/etc/ssh/sshd_config' for setting     this up (the default is not to chroot users). Details     regarding configuring this new option are in the     sshd_config(5) manual page. (BZ#440240)

  - the executables which are part of the OpenSSH FIPS     module which is being validated will check their     integrity and report their FIPS mode status to the     system log or to the terminal. (BZ#467268, BZ#492363)

After installing this update, the OpenSSH server daemon (sshd) will be restarted automatically.

Note: fipscheck update needed for dependencies.

The version of OpenSSH running on the remote host has an information disclosure vulnerability.  A design flaw in the SSH specification could allow a man-in-the-middle attacker to recover up to 32 bits of plaintext from an SSH-protected connection in the standard configuration.  An attacker could exploit this to gain access to sensitive information.

The version of SunSSH running on the remote host has an information disclosure vulnerability.  A design flaw in the SSH specification could allow a man-in-the-middle attacker to recover up to 32 bits of plaintext from an SSH-protected connection in the standard configuration.  An attacker could exploit this to gain access to sensitive information.

Note that this version of SunSSH is also prone to several additional issues but Nessus did not test for them.

Updated openssh packages that fix a security issue, a bug, and add enhancements are now available for Red Hat Enterprise Linux 5.

This update has been rated as having low security impact by the Red Hat Security Response Team.

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 SSH protocol. An attacker able to perform a man-in-the-middle attack may be able to obtain a portion of plain text from an arbitrary ciphertext block when a CBC mode cipher was used to encrypt SSH communication. This update helps mitigate this attack:
OpenSSH clients and servers now prefer CTR mode ciphers to CBC mode, and the OpenSSH server now reads SSH packets up to their full possible length when corruption is detected, rather than reporting errors early, reducing the possibility of successful plain text recovery.
(CVE-2008-5161)

This update also fixes the following bug :

* the ssh client hung when trying to close a session in which a background process still held tty file descriptors open. With this update, this so-called 'hang on exit' error no longer occurs and the ssh client closes the session immediately. (BZ#454812)

In addition, this update adds the following enhancements :

* the SFTP server can now chroot users to various directories, including a user's home directory, after log in. A new configuration option -- ChrootDirectory -- has been added to '/etc/ssh/sshd_config' for setting this up (the default is not to chroot users). Details regarding configuring this new option are in the sshd_config(5) manual page. (BZ#440240)

* the executables which are part of the OpenSSH FIPS module which is being validated will check their integrity and report their FIPS mode status to the system log or to the terminal. (BZ#467268, BZ#492363)

All OpenSSH users are advised to upgrade to these updated packages, which contain backported patches to resolve these issues and add these enhancements. After installing this update, the OpenSSH server daemon (sshd) will be restarted automatically.

The remote host is running a version of Mac OS X 10.5 that does not have Security Update 2009-006 applied.

This security update contains fixes for the following products :

  - AFP Client
  - Adaptive Firewall
  - Apache
  - Apache Portable Runtime
  - ATS
  - Certificate Assistant
  - CoreGraphics
  - CUPS
  - Dictionary
  - DirectoryService
  - Disk Images
  - Event Monitor
  - fetchmail
  - FTP Server
  - Help Viewer
  - International Components for Unicode
  - IOKit
  - IPSec
  - libsecurity
  - libxml
  - OpenLDAP
  - OpenSSH
  - PHP
  - QuickDraw Manager
  - QuickLook
  - FreeRADIUS
  - Screen Sharing
  - Spotlight
  - Subversion

The remote Redhat Enterprise Linux 5 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2009:1287 advisory.

    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 SSH protocol. An attacker able to perform a     man-in-the-middle attack may be able to obtain a portion of plain text from     an arbitrary ciphertext block when a CBC mode cipher was used to encrypt     SSH communication. This update helps mitigate this attack: OpenSSH clients     and servers now prefer CTR mode ciphers to CBC mode, and the OpenSSH server     now reads SSH packets up to their full possible length when corruption is     detected, rather than reporting errors early, reducing the possibility of     successful plain text recovery. (CVE-2008-5161)

    This update also fixes the following bug:

    * the ssh client hung when trying to close a session in which a background     process still held tty file descriptors open. With this update, this     so-called hang on exit error no longer occurs and the ssh client closes     the session immediately. (BZ#454812)

    In addition, this update adds the following enhancements:

    * the SFTP server can now chroot users to various directories, including     a user's home directory, after log in. A new configuration option --     ChrootDirectory -- has been added to /etc/ssh/sshd_config for setting     this up (the default is not to chroot users). Details regarding configuring     this new option are in the sshd_config(5) manual page. (BZ#440240)

    * the executables which are part of the OpenSSH FIPS module which is being     validated will check their integrity and report their FIPS mode status to     the system log or to the terminal. (BZ#467268, BZ#492363)

    All OpenSSH users are advised to upgrade to these updated packages, which     contain backported patches to resolve these issues and add these     enhancements. After installing this update, the OpenSSH server daemon     (sshd) will be restarted automatically.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

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

The remote Tectia SSH server is vulnerable to a flaw within its Cipher-Block Chaining (CBC) mode.  An attacker exploiting this flaw would be able to obtain four (4) plaintext bytes of the encrypted session.  Note: successful attack will result in the SSH session terminating.

According to its banner, the version of SSH installed on the remote host is older than 5.1.  Such versions may allow a local user to hijack X11 sessions because it improperly checks user privileges before re-binding a port.  In order for the attack to be successful, the 'X11UseLocalhost' option would need to be disabled.  By default, the option is enabled.  Further, the OpenSSH service would need to be running on an operating system (such as HP-UX) where the effective user ID is not checked.

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.

SunOS 5.9_x86: Kernel Patch.
Date this patch was last updated by Sun : Nov/03/11

SunOS 5.9: Kernel Patch.
Date this patch was last updated by Sun : Nov/03/11

ID	Name	Product	Family	Severity
206823	Nutanix AHV : Multiple Vulnerabilities (NXSA-AHV-20230302.100173)	Nessus	Misc.	low
197084	Nutanix AOS : Multiple Vulnerabilities (NXSA-AOS-6.8)	Nessus	Misc.	low
187269	Nutanix AHV : Multiple Vulnerabilities (NXSA-AHV-20230302.1011)	Nessus	Misc.	low
180625	Oracle Linux 5 : openssh (ELSA-2009-1287)	Nessus	Oracle Linux Local Security Checks	low
180469	Nutanix AHV : Multiple Vulnerabilities (NXSA-AHV-20230302.207)	Nessus	Misc.	low
78153	F5 Networks BIG-IP : OpenSSH vulnerability (K14609)	Nessus	F5 Networks Local Security Checks	low
73958	GLSA-201405-06 : OpenSSH: Multiple vulnerabilities	Nessus	Gentoo Local Security Checks	medium
73557	AIX OpenSSH Advisory: openssh_advisory.asc	Nessus	AIX Local Security Checks	low
70658	SSH Server CBC Mode Ciphers Enabled	Nessus	Misc.	low
60657	Scientific Linux Security Update : openssh on SL5.x i386/x86_64	Nessus	Scientific Linux Local Security Checks	low
44065	OpenSSH < 5.2 CBC Plaintext Disclosure	Nessus	Misc.	medium
55992	SunSSH < 1.1.1 / 1.3 CBC Plaintext Disclosure	Nessus	Misc.	critical
43781	CentOS 5 : openssh (CESA-2009:1287)	Nessus	CentOS Local Security Checks	low
42433	Mac OS X Multiple Vulnerabilities (Security Update 2009-006)	Nessus	MacOS X Local Security Checks	critical
40837	RHEL 5 : openssh (RHSA-2009:1287)	Nessus	Red Hat Local Security Checks	critical
4761	SSH Tectia CBC Information Disclosure	Nessus Network Monitor	SSH	medium
4598	OpenSSH X11 < 5.1 Session Hijacking	Nessus Network Monitor	SSH	medium
24861	Solaris 9 (x86) : 122301-61	Nessus	Solaris Local Security Checks	high
24858	Solaris 9 (sparc) : 122300-61	Nessus	Solaris Local Security Checks	high

Detections

Analytics

CVE-2008-5161

low

Tenable Plugins

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critical

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