CVE-2026-52766

YesWiki: Unauthenticated arbitrary page deletion via `{{erasespamedcomments}}` action

Published Sep 4, 2026 CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed
Description
YesWiki is a wiki system written in PHP. Prior to version 4.6.6, the {{erasespamedcomments}} wiki action (actions/EraseSpamedCommentsAction.php) accepts a suppr[] array from POST and deletes every wiki page whose tag appears in that array, with no authorization check anywhere in the action body or in the page-deletion path it invokes. Combined with YesWiki's allow-by-default action ACL model, any user who has page write access, which is the default for everyone (default_write_acl='*') on a fresh install can permanently delete arbitrary wiki pages, including the front page, admin pages, and pages owned by other users. This issue has been patched in version 4.6.6.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-6x7x-gcmf-7r8x YesWiki vulnerable to unauthenticated arbitrary page deletion via `{{erasespamedcomments}}` action
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Yeswiki
Yeswiki yeswiki
Vendors & Products Yeswiki
Yeswiki yeswiki
Type Values Removed Values Added
Description YesWiki is a wiki system written in PHP. Prior to version 4.6.6, the {{erasespamedcomments}} wiki action (actions/EraseSpamedCommentsAction.php) accepts a suppr[] array from POST and deletes every wiki page whose tag appears in that array, with no authorization check anywhere in the action body or in the page-deletion path it invokes. Combined with YesWiki's allow-by-default action ACL model, any user who has page write access, which is the default for everyone (default_write_acl='*') on a fresh install can permanently delete arbitrary wiki pages, including the front page, admin pages, and pages owned by other users. This issue has been patched in version 4.6.6.
Title YesWiki: Unauthenticated arbitrary page deletion via `{{erasespamedcomments}}` action
Weaknesses CWE-276
CWE-862
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Sep 9, 2026, 4:01 PM
Reserved
Jun 8, 2026, 5:13 PM
Status
Deferred
Published
Sep 5, 2026, 12:17 AM
Modified
Sep 9, 2026, 5:17 PM