CVE-2026-86142: xmlsoft libxml2 Heap-based Buffer Overflow
CVSS: 7.8v3.1HighAnalyzed
AliasesUBUNTU-CVE-2026-86142DEBIAN-CVE-2026-86142RHSA-2026:80675
Published 05-09-2026Last modified 14-09-2026
Vulnerability summary
CVE-2026-86142 is a high (CVSS 7.8) Heap-based Buffer Overflow vulnerability in xmlsoft libxml2. EPSS estimates a 0.16% chance of exploitation in the next 30 days, higher than 4.4% of scored vulnerabilities.
CVSS score
7.8/10
010
High · v3.1 (NVD)EPSS score
0.16%
0%100%
Low · +0.01 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 5 · Related 1Timeline
- 05-09-2026PublishedVulnerability first disclosed.
- 14-09-2026Last modifiedVulnerability information updated.
Description
In libxml2 before 2.15.4, there is a heap-based buffer overflow in xmlXPtrEvalXPtrPart because of xmlXPtrEval xpointer length saturation.
CVSS metrics
5 scores · 5 sources · 1 versionHigh 7.8Preferred score · NVD (NIST)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HSources5 sources · 6.9–7.8
- CVE.orgCNA6.9MediumCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:LDiffers
- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · Red hatEcosystem advisory · calculated6.9MediumCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:LDiffers
EPSS trend
Probability
0.16%
Chance of exploitation in the next 30 days
Percentile
4%
Versus all other CVEs
30-day change
+0.01 pp
From 0.15% on 20-09-2026
20-09-202620-10-2026
EPSS score0.16%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Redhat6 products
- libxml2< 0:2.9.7-21.el8_10.10
- libxml2-debuginfo< 0:2.9.7-21.el8_10.10
- libxml2-debugsource< 0:2.9.7-21.el8_10.10
- libxml2-devel< 0:2.9.7-21.el8_10.10
- python3-libxml2< 0:2.9.7-21.el8_10.10
Debian1 product
- libxml2All versions (No fix recorded) | < 2.15.4+dfsg-1
Ubuntu1 product
- libxml2< 2.9.1+dfsg1-3ubuntu4.13+esm13 | < 2.9.3+dfsg1-1ubuntu0.7+esm14 | < 2.9.4+dfsg1-6.1ubuntu1.9+esm9 | < 2.9.10+dfsg-5ubuntu0.20.04.10+esm6 | < 2.9.13+dfsg-1ubuntu0.14 | < 2.9.14+dfsg-1.3ubuntu3.10 | < 2.15.2+dfsg-0.1ubuntu0.3
Xmlsoft1 product
- libxml2< 2.15.4
4 vendors · 9 products
