CVE-2026-6653

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugs.launchpad.net/ubuntu/+source/libxml2/+bug/2141260	Exploit Issue Tracking Third Party Advisory
https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1058	Exploit Issue Tracking Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:xmlsoft:libxml2:*:*:*:*:*:*:*:*

History

14 Jul 2026, 16:00

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8
CPE		cpe:2.3:a:xmlsoft:libxml2::::::::
References	~~() https://bugs.launchpad.net/ubuntu/+source/libxml2/+bug/2141260 -~~	() https://bugs.launchpad.net/ubuntu/+source/libxml2/+bug/2141260 - Exploit, Issue Tracking, Third Party Advisory
References	~~() https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1058 -~~	() https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1058 - Exploit, Issue Tracking, Patch
First Time		Xmlsoft libxml2 Xmlsoft

22 Jun 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-22 14:17

Updated : 2026-07-14 16:00

NVD link : CVE-2026-6653

Mitre link : CVE-2026-6653

CVE.ORG link : CVE-2026-6653

JSON object : View

Products Affected

xmlsoft

libxml2

CWE

CWE-416

Use After Free

CWE-611

Improper Restriction of XML External Entity Reference

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