CVE-2026-11979 LOW

CVE-2026-11979: Stack-Based Buffer Overflow in libxml2

Vendor Xmlsoft
Product libxml2
Weakness CWE-121
Published June 29, 2026
Last update June 29, 2026

CVSS base score

1.8/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:L/SC:L/SI:L/SA:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

June 29, 2026 CVE published
June 29, 2026 Record updated