Amazon Linux 2023 Security Advisory: ALAS2023-2026-1992
Advisory Released Date: 2026-08-04
Advisory Updated Date: 2026-08-04
Severity:
Medium
Issue Overview:
libxml2 is vulnerable to multiple stack-based buffer overflows in the xmlcatalog utility when running in --shell mode. The usershell() function processes user input using fixed-size stack buffers without proper bounds checking.
By supplying an overly long input line, an attacker can overflow internal buffers (command, arg, and argv) during input parsing. This results in memory corruption within the stack frame.
Successful exploitation may cause a crash or potentially allow arbitrary code execution in the context of the xmlcatalog process.
This issue has been fixed in the commit c2e233fc.
NOTE:
The maintainers of this project did not agree that this issue is a vulnerability and considered it a bug. (CVE-2026-11979)
Affected Packages:
libxml2
Issue Correction:
Run dnf update libxml2 --releasever 2023.12.20260803 or dnf update --advisory ALAS2023-2026-1992 --releasever 2023.12.20260803 to update your system.
More information on how to update your system can be found on this page: Amazon Linux 2023 documentation
New Packages:
aarch64:
libxml2-debugsource-2.10.4-1.amzn2023.0.20.aarch64
libxml2-static-2.10.4-1.amzn2023.0.20.aarch64
libxml2-debuginfo-2.10.4-1.amzn2023.0.20.aarch64
python3-libxml2-debuginfo-2.10.4-1.amzn2023.0.20.aarch64
python3-libxml2-2.10.4-1.amzn2023.0.20.aarch64
libxml2-devel-2.10.4-1.amzn2023.0.20.aarch64
libxml2-2.10.4-1.amzn2023.0.20.aarch64
src:
libxml2-2.10.4-1.amzn2023.0.20.src
x86_64:
libxml2-debuginfo-2.10.4-1.amzn2023.0.20.x86_64
python3-libxml2-debuginfo-2.10.4-1.amzn2023.0.20.x86_64
libxml2-static-2.10.4-1.amzn2023.0.20.x86_64
libxml2-debugsource-2.10.4-1.amzn2023.0.20.x86_64
libxml2-devel-2.10.4-1.amzn2023.0.20.x86_64
python3-libxml2-2.10.4-1.amzn2023.0.20.x86_64
libxml2-2.10.4-1.amzn2023.0.20.x86_64