Vulnerability · Published Sep 4, 2026 · Assigned by GitHub_M
CVE-2026-52774Reflected XSS via Unescaped `id` Parameter in Bazar Widget HTML Attributes in YesWiki
Medium 6.1
In plain English
A medium-severity security flaw in yeswiki from YesWiki. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei, public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
YesWiki is a wiki system written in PHP. Prior to version 4.6.6, YesWiki's Bazar widget handler reflects the id GET parameter into HTML attributes using strip_tags() only. Because strip_tags() does not escape double quotes, an attacker can break out of the attribute value, inject an event handler such as onmouseover, and execute arbitrary JavaScript in the victim's browser. This issue is reachable without authentication. During validation, the vulnerable widget route returned the injected HTML for both /HomePage/widget?id=... and /NoSuchPage/widget?id=..., which shows that no login, no page ownership, no edit rights, and not even a valid page tag were required. The only routing prerequisite observed was that the Bazar extension is enabled and the request includes an id parameter. This issue has been patched in version 4.6.6.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Packagist | yeswiki/yeswiki | 4.6.6 | GHSA-r5xw-gcgw-hwp5 |
Affected products (as reported)
Weakness: CWE-80 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
References
- https://github.com/YesWiki/yeswiki/security/advisories/GHSA-r5xw-gcgw-hwp5 x_refsource_CONFIRM
- https://github.com/YesWiki/yeswiki/commit/1aa2710c7505630b858f2142a65f9441bfaba2b2 x_refsource_MISC
- https://github.com/YesWiki/yeswiki/releases/tag/v4.6.6 x_refsource_MISC