CVE-2026-6653

libxml2: Use after free in xmlParseInternalSubset via improper entity resolution handling

At a glance

Severity: HIGH 7.0
EPSS: EPSS 0.36 % · percentile 29 (2026-10-27)
State: PUBLISHED
Published: 2026-06-22
Updated: 2026-06-22
Assigner: canonical
NVD status: Analyzed

Description

Use After Free in libxml2's xmlParseInternalSubset from GNOME libxml2 version 2.9.11 to 2.11.0 allows a remote attacker to cause a denial-of-service via maliciously crafted XML input with improper entity resolution handling.

Scores

Version	Score	Vector	Scored by
CVSS 4.0	HIGH 7.0	CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N/E:P	canonical
CVSS 4.0	HIGH 7.0	CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X	NVD · security@ubuntu.com (Secondary)
CVSS 3.1	CRITICAL 9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	NVD · nvd@nist.gov (Primary)

Weaknesses (CWE)

European references

ENISA EUVD · EUVD-2026-38232
GCVE · GCVE-0-2026-6653

CERT-FR advisories

CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2026-AVI-1249 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:xmlsoft:libxml2:*:*:*:*:*:*:*:* ≥ 2.9.11 ≤ 2.11.0

Affected products

Product	Versions
GNOME · libxml2	affected 2.9.11 < 2.11.0

References

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD