CVE-2026-52766
CRITICAL
NVD
CVSS Score
9.1
Severity
CRITICAL
Published
Sep 05, 2026
Vendor
unknown
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.