Out-of-bounds read in xmlsoft libxml2
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · None · Low
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA libxml2 (xmlsoft) Fixed in 2.15.4
Red Hat 1 advisory
- RHSA-2026:64463 Released 2026-09-06 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images libxml2-16-2.15.4-0.1.hum1@aarch64, libxml2-16-2.15.4-0.1.hum1@x86_64, libxml2-2.15.4-0.1.hum1@aarch64 +8
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
xmlsoft libxml2 2.15.4
8 records Highest priority Priority LOW 8 LOW
Other records, highest priority first
- TI-2026-58934 In libxml2 before 2.15.4, xmlSnprintfElements in valid.c has a strcat stack-based buffer overflow.Priority LOW 36
- TI-2026-58936 Heap-based buffer overflow in xmlsoft libxml2Priority LOW 35
- TI-2026-58933 In libxml2 before 2.15.4, xmlURIEscapeStr in uri.c has an integer overflow.Priority LOW 35
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Hardened Images | Fixed | RHSA-2026:64463 |
Not affected: 8 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat Hardened Images
- Red Hat OpenShift Container Platform 4
- Red Hat OpenShift Container Platform 5
Timeline
- 2026-10-02 Threatist record created from CVE-2026-86137
- 2026-10-03 Alias added: GHSA-cq7w-3xjv-g47g
- 2026-11-07 Affected versions changed · Red Hat
References
More xmlsoft Libxml2 vulnerabilities
- TI-2020-06117 xmlStringLenDecodeEntities in parser.c in libxml2 2.9.10 has an infinite loop in a certain end-of-file situation. CVSS 3.1HIGH 7.5
- TI-2025-05441 Libxml2: integer overflow in xmlbuildqname() leads to stack buffer overflow in libxml2 CVSS 3.1HIGH 7.5
- TI-2024-22792 An issue was discovered in xmllint (from libxml2) before 2.11.8 and 2.12.x before 2.12.7. CVSS 3.1HIGH 7.5
- TI-2017-06514 libxml2 20904-GITv2.9.4-16-g0741801 is vulnerable to a heap-based buffer over-read in the… CVSS 3.1HIGH 7.5
- TI-2022-19140 An issue was discovered in libxml2 before 2.10.3. CVSS 3.1HIGH 7.5
- TI-2025-23491 Out-of-bounds read in xmlsoft libxml2 CVSS 3.1HIGH 7.5
Sources
- CVE-2026-86137 · CVE Program
- CVE-2026-86137 · NVD
- FIRST EPSS
- GHSA-cq7w-3xjv-g47g · GitHub Advisory Database · CC BY 4.0
- CVE-2026-86137 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences