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.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-r5xw-gcgw-hwp5 YesWiki Vulnerable to Reflected XSS via Unescaped `id` Parameter in Bazar Widget HTML Attributes
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Sat, 05 Sep 2026 00:00:00 +0000

Type Values Removed Values Added
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.
Title Reflected XSS via Unescaped `id` Parameter in Bazar Widget HTML Attributes in YesWiki
Weaknesses CWE-80
References
Metrics cvssV3_1

{'score': 6.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-09-04T23:51:19.336Z

Reserved: 2026-06-08T17:13:43.064Z

Link: CVE-2026-52774

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-05T00:17:20.380

Modified: 2026-09-05T00:17:20.380

Link: CVE-2026-52774

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-05T01:30:17Z

Weaknesses