Vulnerability · Published Jan 30, 2026 · Assigned by mitre
CVE-2026-25210
Medium 6.9
In plain English
A medium-severity integer overflow in libexpat from libexpat project. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)6.9Medium
Exploit odds (30 days)0.2%top 88.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
In libexpat before 2.7.4, the doContent function does not properly determine the buffer size bufSize because there is no integer overflow check for tag buffer reallocation.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | expat | 2.7.4-r0 | ALPINE-CVE-2026-25210 |
| Alpine:v3.21 | expat | 2.7.4-r0 | ALPINE-CVE-2026-25210 |
| Alpine:v3.22 | expat | 2.7.4-r0 | ALPINE-CVE-2026-25210 |
| Alpine:v3.23 | expat | 2.7.4-r0 | ALPINE-CVE-2026-25210 |
| Alpine:v3.24 | expat | 2.7.4-r0 | ALPINE-CVE-2026-25210 |
| Alpine:v3.24 | qt6-qtwebengine | 6.11.1-r2 | ALPINE-CVE-2026-25210 |
| Debian:12 | expat | 2.5.0-1+deb12u4 | DEBIAN-CVE-2026-25210 |
| Debian:13 | expat | 2.8.2-1~deb13u1 | DEBIAN-CVE-2026-25210 |
| Debian:14 | expat | 2.7.4-1 | DEBIAN-CVE-2026-25210 |
| Ubuntu:22.04:LTS | cadaver | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:24.04:LTS | cadaver | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:25.10 | cadaver | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.04:LTS | cadaver | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.10 | cadaver | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:22.04:LTS | expat | 2.4.7-1ubuntu0.7 | UBUNTU-CVE-2026-25210 |
| Ubuntu:24.04:LTS | expat | 2.6.1-2ubuntu0.4 | UBUNTU-CVE-2026-25210 |
| Ubuntu:24.04:LTS | expat | 2.6.1-2ubuntu0.4 | USN-8022-2 |
| Ubuntu:25.10 | expat | 2.7.1-2ubuntu0.2 | UBUNTU-CVE-2026-25210 |
| Ubuntu:22.04:LTS | insighttoolkit4 | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:22.04:LTS | matanza | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:24.04:LTS | matanza | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:25.10 | matanza | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.04:LTS | matanza | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.10 | matanza | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:25.10 | swish-e | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.10 | swish-e | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:22.04:LTS | tdom | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:24.04:LTS | tdom | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:25.10 | tdom | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.04:LTS | tdom | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.10 | tdom | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:22.04:LTS | wbxml2 | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:24.04:LTS | wbxml2 | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:25.10 | wbxml2 | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.04:LTS | wbxml2 | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.10 | wbxml2 | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:25.10 | xmlrpc-c | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.04:LTS | xmlrpc-c | no fix listed | UBUNTU-CVE-2026-25210 |
| Ubuntu:26.10 | xmlrpc-c | no fix listed | UBUNTU-CVE-2026-25210 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| libexpat project | libexpat | 0 – before 2.7.4 |
Weakness: CWE-190 · Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L