CVE-2009-1956 Integer overflow in n/a
Remote attackers can cause application crashes or leak sensitive information via crafted input due to an off-by-one error in the APR-util library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2009-1956?
CVE-2009-1956 is a medium-severity vulnerability in Apache Http Server, published on 6 Jun 2009. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-189
Which versions are affected by CVE-2009-1956?
It affects 3 products.
Products include Apache Apr-Util, Apache Http Server, Canonical Ubuntu Linux.
How do I fix CVE-2009-1956?
Upgrade to a fixed version.
Is CVE-2009-1956 being exploited?
There is no known exploitation of CVE-2009-1956 in the wild and no public exploit code.
Other vulnerabilities in Apache Http Server
- CVE-2009-2412 Integer overflow in n/a
- CVE-2026-32327 Apache Portable Runtime Utility: apr-util XML stack recursion crash
- CVE-2026-34191 Apache Portable Runtime Utility: SQL Injection in apr_dbd_oracle
- CVE-2025-49506 Apache Portable Runtime Utility: apr_password_validate() vulnerable to timing attack
- CVE-2026-34501 Apache Portable Runtime Utility: Heap buffer overflow in APR redis client
Sources
Also known as DEBIAN-CVE-2009-1956, GHSA-4wj9-j34x-wjxp.