CVE-2022-25235
A public proof of concept exists; no exploitation attested.
- Published2022-02-16
- WeaknessCWE-116
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
xmltok_impl.c in Expat (aka libexpat) before 2.4.5 lacks certain validation of encoding, such as checks for whether a UTF-8 character is valid in a certain context.
Timeline
dates in UTC- 2022-02-1601:15CVE publishedNVD
- 2026-10-2319:23First public proof of conceptPoC-in-GitHub
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2022-25235?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2022-25235?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 10.0 | = 10.0 | no fix published | NVD |
| 11.0 | = 11.0 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 34.x | = 34 | no fix published | NVD |
| 35.x | = 35 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 12.2 | = 12.2.1.3.0 | no fix published | NVD |
| 12.2 | = 12.2.1.4.0 | no fix published | NVD |
3 more products in the sources.
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Packages
- expatAlmaLinux:8all versions · fixed in 2.2.5-8.el8_6.2and 1 other package
- firefoxAlmaLinux:8all versions · fixed in 91.7.0-3.el8_5.alma
- mingw32-expatAlmaLinux:8all versions · fixed in 2.4.8-1.el8and 1 other package
- thunderbirdAlmaLinux:8all versions · fixed in 91.7.0-2.el8_5.alma.plus
- thunderbirdAlmaLinux:8all versions · fixed in 91.7.0-2.el8_5.alma
- xmlrpc-c-c++AlmaLinux:8all versions · fixed in 1.51.0-5.el8_5.1and 2 other packages
Fix
Advisories and patches
- github.comPatch
- www.oracle.comPatch
Detection
read 2026-10-23 19:23 UTC- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- 1 repository, unverifiedSatheesh575555/external_expat_AOSP10_r33_CVE-2022-25235 PoC-in-GitHub
Sources
- CISA-ADPSSVC decisionnone2025-04-23
- OpenCVESSVC decisionnone—
- CISA-ADPCVSS 3.19.82025-05-05
- NVDCVSS 3.19.8read 2026-10-23
- NVDCVSS 2.07.5read 2026-10-23
- CISA-ADPweakness (CWE)CWE-1162025-05-05
- NVDweakness (CWE)CWE-116read 2026-10-23
- FIRST EPSSEPSS score5.0 %2026-10-23
- PoC-in-GitHubproof of concept1read 2026-10-23
- OSVaffected packages—
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Published
- 2022-02-16
- Last Modified
- 2026-10-14
- NVD status
- Modified
Frequently asked questions
What is CVE-2022-25235?
Is CVE-2022-25235 actively exploited?
What is the CVSS score for CVE-2022-25235?
Running expat? Hear about its next vulnerability
Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».
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Go further
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.