CVE-2026-11979
libxml2: libxml2: Arbitrary code execution in xmlcatalog utility via buffer overflow
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · June 29, 2026
Updated · November 3, 2026
Description
A flaw was found in libxml2, specifically within the xmlcatalog utility when operating in shell mode. An attacker can exploit multiple stack-based buffer overflows by providing an excessively long input line. This leads to memory corruption, which may cause the application to crash or potentially allow the attacker to execute arbitrary code within the context of the xmlcatalog process.
Statement
This Moderate impact flaw in libxml2 affects the xmlcatalog utility when operating in --shell mode. Exploitation requires an attacker to provide specially crafted, excessively long input, leading to stack-based buffer overflows. This vulnerability is limited to scenarios where an attacker can control input to the xmlcatalog utility, reducing its overall exposure in typical Red Hat deployments.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-120 · Buffer Copy without Checking Size of Input