libxml2's xmlParseInternalSubset · Use After Free
Affects libxml2Source GCVE Database
Public exploit available · CVSS 7.0 High · fixed in 2.9.13+dfsg-1ubuntu0.12 : patch libxml2 as a priority.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 28% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.9.13+dfsg-1ubuntu0.12, 2.9.14+dfsg-1.3ubuntu3.8
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:PExploitation evidence
Disclosed: evidence found.
CVE published 22 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
CVSS exploit maturity: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade the Ubuntu libxml2 to 2.9.13+dfsg-1ubuntu0.12 (package) or 2.9.14+dfsg-1.3ubuntu3.8 (package).
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 24.04 LTSlibxml2pkg:deb/ubuntu/libxml2?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 22.04 LTSlibxml2pkg:deb/ubuntu/libxml2?arch=source&distro=jammyOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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.
References
- ubuntu.com/security/CVE-2026-6653 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-6653 (opens in a new tab)
- gitlab.gnome.org/GNOME/libxml2/-/work_items/1058 (opens in a new tab)
- bugs.launchpad.net/ubuntu/+source/libxml2/+bug/2141260 (opens in a new tab)
- ubuntu.com/security/notices/USN-8456-1 (opens in a new tab)