CVE-2026-11979CWE-121

Stack-Based Buffer Overflow in libxml2

Low · published June 29, 2026

CVSS v4.0
1.8
EPSS
0%
Percentile
3.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
1.8 · LOW
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
EPSS
0.00148 · 3.7th percentile
Weakness
CWE-121 · Stack-based Buffer Overflow
Published
2026-06-29T13:21Z
EPSS history
Timeline
  • 29 JUN 13:21Z
    Stack-Based Buffer Overflow in libxml2
    cvelistv5