CVE-2026-52766
YesWiki vulnerable to unauthenticated arbitrary page deletion via `{{erasespamedcomments}}` action
Impact
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 packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| composer | yeswiki/yeswiki | < 4.6.6 | 4.6.6 |