Medium severity · published Sep 5, 2026
CVE-2026-86137
In libxml2 before 2.15.4, xmlFAParsePosCharGroup has an out-of-bounds read, aka an out-of-bounds read in the NXT macro in xmlregexp
6.1
CVSS
0.2%
EPSS
No
On KEV
Description
In libxml2 before 2.15.4, xmlFAParsePosCharGroup has an out-of-bounds read, aka an out-of-bounds read in the NXT macro in xmlregexp.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:L
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libxml2 · xmlsoft
before 2.15.4 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-86137
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-86137
Patch
https://github.com/GNOME/libxml2/commit/76fe08d97de88bfaef2f7d5cd27f11954cc5bee2
Release Notes
https://github.com/GNOME/libxml2/compare/v2.15.3...v2.15.4
Exploit
https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1099
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