CVE-2011-1951

Severity: medium (CVSS 4.3 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2011-07-11 · updated 2026-06-16
Weakness: CWE-399

Description

lib/logmatcher.c in Balabit syslog-ng before 3.2.4, when the global flag is set and when using PCRE 8.12 and possibly other versions, allows remote attackers to cause a denial of service (memory consumption) via a message that does not match a regular expression.

Affected products

OneIdentity Syslog-Ng: before 3.2.4 — fixed in 3.2.4

How to fix

Upgrade to a fixed version: OneIdentity Syslog-Ng 3.2.4. Check the vendor advisory for mitigations.

References

http://git.balabit.hu/?p=bazsi/syslog-ng-3.2.git%3Ba=commit%3Bh=09710c0b105e579d35c7b5f6c66d1ea5e3a3d3ff
http://lists.fedoraproject.org/pipermail/package-announce/2011-June/062107.html
http://secunia.com/advisories/45122
http://www.openwall.com/lists/oss-security/2011/05/26/1
http://www.securityfocus.com/bid/47800
https://bugzilla.redhat.com/show_bug.cgi?id=709088
http://git.balabit.hu/?p=bazsi/syslog-ng-3.2.git%3Ba=commit%3Bh=09710c0b105e579d35c7b5f6c66d1ea5e3a3d3ff
http://lists.fedoraproject.org/pipermail/package-announce/2011-June/062107.html
http://secunia.com/advisories/45122
http://www.openwall.com/lists/oss-security/2011/05/26/1
http://www.securityfocus.com/bid/47800
https://bugzilla.redhat.com/show_bug.cgi?id=709088

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