CVE-2009-1956

Severity: medium (CVSS 6.4 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 12.0% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2009-06-08 · updated 2026-06-16
Weakness: CWE-189

Description

Off-by-one error in the apr_brigade_vprintf function in Apache APR-util before 1.3.5 on big-endian platforms allows remote attackers to obtain sensitive information or cause a denial of service (application crash) via crafted input.

Affected products

Apache Apr-Util: through 1.3.4
Apache HTTP Server: from 2.2.0 before 2.2.12 — fixed in 2.2.12
Canonical Ubuntu Linux: 6.06, 8.04, 8.10, 9.04

How to fix

Upgrade to a fixed version: Apache HTTP Server 2.2.12. Check the vendor advisory for mitigations.

References

http://lists.apple.com/archives/security-announce/2009/Nov/msg00000.html
http://marc.info/?l=bugtraq&m=129190899612998&w=2
http://secunia.com/advisories/34724
http://secunia.com/advisories/35284
http://secunia.com/advisories/35395
http://secunia.com/advisories/35487
http://secunia.com/advisories/35565
http://secunia.com/advisories/35710
http://secunia.com/advisories/35797
http://secunia.com/advisories/35843
http://secunia.com/advisories/37221
http://security.gentoo.org/glsa/glsa-200907-03.xml

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