XSS in Semanticmediawiki

CVE-2026-77606

Semantic MediaWiki is a free, open-source extension to MediaWiki that lets users store and query data within the wiki's pages. Prior to version 7.2.0, when `headers=plain`, table header text was emitted into `<th>` via a raw HTML path. User-controlled `mainlabel` content could therefore become executable HTML. Version 7.2.0 fixes the issue.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (18.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 18th percentile — 18.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-77606: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-77606?
CVE-2026-77606 is a medium-severity vulnerability in Semanticmediawiki, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-09-18.
How severe is CVE-2026-77606?
Medium severity. CVSS v3 base score is 6.1 out of 10.