CVE-2026-76781: libxml2 NULL Pointer Dereference
CVSS: 5.5v3.1MediumAwaiting analysis
AliasesRHSA-2026:57604UBUNTU-CVE-2026-76781DEBIAN-CVE-2026-76781
Published 17-09-2026Last modified 24-09-2026
Vulnerability summary
CVE-2026-76781 is a medium (CVSS 5.5) NULL Pointer Dereference vulnerability in libxml2. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 5.5% of scored vulnerabilities.
CVSS score
5.5/10
010
Medium · v3.1 (CVE.org)EPSS score
0.17%
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 1 · Related 1Timeline
- 17-09-2026PublishedVulnerability first disclosed.
- 24-09-2026Last modifiedVulnerability information updated.
Description
A flaw was found in libxml2. A local user or an attacker providing a specially crafted XML catalog can trigger a NULL pointer dereference during XML catalog parsing. This occurs when a `nextCatalog` element lacks its mandatory `catalog` attribute, leading to the application crashing and causing a Denial of Service (DoS).
CVSS metrics
5 scores · 5 sources · 1 versionMedium 5.5Preferred score · CVE.org (CNA)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:HSourcesAll 5 agree
- OSV · Red hatEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- NVDNIST5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.17%
Chance of exploitation in the next 30 days
Percentile
6%
Versus all other CVEs
30-day change
+0.01 pp
From 0.16% on 20-09-2026
20-09-202620-10-2026
EPSS score0.17%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Redhat5 products
- libxml2< 0:2.15.3-0.1.3.hum1
- libxml2-16< 0:2.15.3-0.1.3.hum1
- libxml2-devel< 0:2.15.3-0.1.3.hum1
- libxml2-static< 0:2.15.3-0.1.3.hum1
- python3-libxml2< 0:2.15.3-0.1.3.hum1
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
3 vendors · 7 products
References
13 links- images.redhat.comARTICLE
