Debian DSA-2125-1 : openssl - buffer overflow

High Nessus Plugin ID 50696

New! Vulnerability Priority Rating (VPR)

Tenable calculates a dynamic VPR for every vulnerability. VPR combines vulnerability information with threat intelligence and machine learning algorithms to predict which vulnerabilities are most likely to be exploited in attacks. Read more about what VPR is and how it's different from CVSS.

VPR Score: 6.7

Synopsis

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

Description

A flaw has been found in the OpenSSL TLS server extension code parsing which on affected servers can be exploited in a buffer overrun attack.
This allows an attacker to cause an application crash or potentially to execute arbitrary code.

However, not all OpenSSL based SSL/TLS servers are vulnerable: a server is vulnerable if it is multi-threaded and uses OpenSSL's internal caching mechanism. In particular the Apache HTTP server (which never uses OpenSSL internal caching) and Stunnel (which includes its own workaround) are NOT affected.

Solution

Upgrade the openssl packages.

This upgrade fixes this issue. After the upgrade, any services using the openssl libraries need to be restarted. The checkrestart script from the debian-goodies package or lsof can help to find out which services need to be restarted.

A note to users of the tor packages from the Debian backports or Debian volatile: this openssl update causes problems with some versions of tor. You need to update to tor 0.2.1.26-4~bpo50+1 or 0.2.1.26-1~lennyvolatile2, respectively. The tor package version 0.2.0.35-1~lenny2 from Debian stable is not affected by these problems.

For the stable distribution (lenny), the problem has been fixed in openssl version 0.9.8g-15+lenny9.

See Also

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=603709

https://www.debian.org/security/2010/dsa-2125

Plugin Details

Severity: High

ID: 50696

File Name: debian_DSA-2125.nasl

Version: 1.15

Type: local

Agent: unix

Published: 2010/11/24

Updated: 2021/01/04

Dependencies: 12634

Risk Information

Risk Factor: High

VPR Score: 6.7

CVSS v2.0

Base Score: 7.6

Temporal Score: 6.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C

Temporal Vector: CVSS2#E:ND/RL:OF/RC:C

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:openssl, cpe:/o:debian:debian_linux:5.0

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

Exploit Available: false

Exploit Ease: No known exploits are available

Patch Publication Date: 2010/11/22

Reference Information

CVE: CVE-2010-3864

BID: 44884

DSA: 2125