CVE-2026-103439 json
Various rawParams() and escaped() updates to prevent XSS in Wikibase extension
published last mo. modified last mo. also EUVD-2026-90211
- cvss
- 0.3
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.1%
- EPSS 0.1% chance of exploitation in 30 days, percentile 1%
- public exploits
- 0
- none known
Summary
Improper neutralization of Script-Related HTML tags in a web page (basic XSS) vulnerability in The Wikimedia Foundation MediaWiki Wikbase extension allows Cross-Site Scripting (XSS).
This issue affects MediaWiki Wikbase extension: 1.46, 1.45, and 1.43.
Is CVE-2026-103439 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.11% chance of exploitation in the next 30 days, higher than 1% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 0.3 | CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:P/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/E:P/S:N/AU:Y/R:U/V:D/RE:M/U:Amber |
| CNA | 4.0 | 0.3 | CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:P/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:N/AU:Y/R:U/V:D/RE:M/U:Amber |
Affected products
- The Wikimedia Foundation MediaWiki Wikbase extension
Classification
- Weakness
-
- CWE-80 Improper Neutralization of Script-Related HTML Tags in a Web Page
References
Sources
- CVE List CVE-2026-103439
- NVD CVE-2026-103439
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.