CVE-2026-1757: Libxml2: memory leak leading to local denial of service in xmllint interactive shell

Severity: medium (CVSS 6.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-02-02 · updated 2026-09-01
Weakness: CWE-401

Description

A flaw was identified in the interactive shell of the xmllint utility, part of the libxml2 project, where memory allocated for user input is not properly released under certain conditions. When a user submits input consisting only of whitespace, the program skips command execution but fails to free the allocated buffer. Repeating this action causes memory to continuously accumulate. Over time, this can exhaust system memory and terminate the xmllint process, creating a denial-of-service condition on the local system.

Affected products

Red Hat OpenShift Container Platform 4.18: all versions
Red Hat Enterprise Linux 10: all versions
Red Hat Enterprise Linux 7: all versions
Red Hat Enterprise Linux 8: all versions
Red Hat Enterprise Linux 9: all versions
Red Hat Hardened Images: all versions — fixed in 2.15.2-0.3.hum1
Red Hat JBoss Core Services: all versions

How to fix

Upgrade to a fixed version: Red Hat Hardened Images 2.15.2-0.3.hum1. Check the vendor advisory for mitigations.

References

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