CVE-2026-52766
YesWiki: Unauthenticated arbitrary page deletion via `{{erasespamedcomments}}` action
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.
- Affected
- YesWiki · yeswiki
- CVSS v3.1 GITHUB
- 9.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H - EPSS
- 0.58% chance of exploitation in the next 30 days, 47th percentile
- Published
- 2026-09-04
- Updated
- 2026-09-09