Debian DSA-2894-1 : openssh - security update

medium Nessus Plugin ID 73350
New! Plugin Severity Now Using CVSS v3

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Synopsis

The remote Debian host is missing a security-related update.

Description

Two vulnerabilities were discovered in OpenSSH, an implementation of the SSH protocol suite. The Common Vulnerabilities and Exposures project identifies the following problems :

- CVE-2014-2532 Jann Horn discovered that OpenSSH incorrectly handled wildcards in AcceptEnv lines. A remote attacker could use this issue to trick OpenSSH into accepting any environment variable that contains the characters before the wildcard character.

- CVE-2014-2653 Matthew Vernon reported that if a SSH server offers a HostCertificate that the ssh client doesn't accept, then the client doesn't check the DNS for SSHFP records. As a consequence a malicious server can disable SSHFP-checking by presenting a certificate.

Note that a host verification prompt is still displayed before connecting.

Solution

Upgrade the openssh packages.

For the oldstable distribution (squeeze), these problems have been fixed in version 1:5.5p1-6+squeeze5.

For the stable distribution (wheezy), these problems have been fixed in version 1:6.0p1-4+deb7u1.

See Also

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=742513

https://security-tracker.debian.org/tracker/CVE-2014-2532

https://security-tracker.debian.org/tracker/CVE-2014-2653

https://packages.debian.org/source/squeeze/openssh

https://packages.debian.org/source/wheezy/openssh

https://www.debian.org/security/2014/dsa-2894

Plugin Details

Severity: Medium

ID: 73350

File Name: debian_DSA-2894.nasl

Version: 1.12

Type: local

Agent: unix

Published: 4/7/2014

Updated: 1/11/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Low

Score: 3.7

CVSS v2

Risk Factor: Medium

Base Score: 5.8

Temporal Score: 4.3

Vector: AV:N/AC:M/Au:N/C:P/I:P/A:N

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Medium

Base Score: 4.9

Temporal Score: 4.3

Vector: CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:openssh, cpe:/o:debian:debian_linux:6.0, cpe:/o:debian:debian_linux:7.0

Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 4/5/2014

Reference Information

CVE: CVE-2014-2532, CVE-2014-2653

BID: 66355, 66459

DSA: 2894