Debian DSA-1571-1 : openssl - predictable random number generator

high Nessus Plugin ID 32305

Synopsis

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

Description

Luciano Bello discovered that the random number generator in Debian's openssl package is predictable. This is caused by an incorrect Debian-specific change to the openssl package (CVE-2008-0166 ). As a result, cryptographic key material may be guessable.

This is a Debian-specific vulnerability which does not affect other operating systems which are not based on Debian. However, other systems can be indirectly affected if weak keys are imported into them.

It is strongly recommended that all cryptographic key material which has been generated by OpenSSL versions starting with 0.9.8c-1 on Debian systems is recreated from scratch. Furthermore, all DSA keys ever used on affected Debian systems for signing or authentication purposes should be considered compromised; the Digital Signature Algorithm relies on a secret random value used during signature generation.

The first vulnerable version, 0.9.8c-1, was uploaded to the unstable distribution on 2006-09-17, and has since that date propagated to the testing and current stable (etch) distributions. The old stable distribution (sarge) is not affected.

Affected keys include SSH keys, OpenVPN keys, DNSSEC keys, and key material for use in X.509 certificates and session keys used in SSL/TLS connections. Keys generated with GnuPG or GNUTLS are not affected, though.

A detector for known weak key material will be published at :

(OpenPGP signature)

Instructions how to implement key rollover for various packages will be published at :

https://www.debian.org/security/key-rollover/

This website will be continuously updated to reflect new and updated instructions on key rollovers for packages using SSL certificates.
Popular packages not affected will also be listed.

In addition to this critical change, two other vulnerabilities have been fixed in the openssl package which were originally scheduled for release with the next etch point release: OpenSSL's DTLS (Datagram TLS, basically 'SSL over UDP') implementation did not actually implement the DTLS specification, but a potentially much weaker protocol, and contained a vulnerability permitting arbitrary code execution (CVE-2007-4995 ). A side channel attack in the integer multiplication routines is also addressed (CVE-2007-3108 ).

Solution

Upgrade the openssl package and subsequently regenerate any cryptographic material, as outlined above.

For the stable distribution (etch), these problems have been fixed in version 0.9.8c-4etch3.

See Also

https://security-tracker.debian.org/tracker/CVE-2008-0166

http://security-cdn.debian.org/project/extra/dowkd/dowkd.pl.gz.asc

https://security-tracker.debian.org/tracker/CVE-2007-4995

https://security-tracker.debian.org/tracker/CVE-2007-3108

https://www.debian.org/security/2008/dsa-1571

Plugin Details

Severity: High

ID: 32305

File Name: debian_DSA-1571.nasl

Version: 1.24

Type: local

Agent: unix

Published: 5/13/2008

Updated: 1/4/2021

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5.1

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.4

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

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:openssl, cpe:/o:debian:debian_linux:4.0

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/13/2008

Exploitable With

Core Impact

Reference Information

CVE: CVE-2008-0166

CWE: 310

DSA: 1571