YesWiki is a wiki system written in PHP. From version 4.2.0 to before version 4.6.6, ApiController::deletePage() interpolates a page tag retrieved from the database into a DELETE FROM …_links WHERE to_tag = '$tag' query without escaping. The page tag is attacker-controlled — the POST /api/pages/{tag} API accepts arbitrary URL-encoded values, including single quotes, and stores them. A low-privilege authenticated user can therefore create a page whose tag is a SQL fragment, make the page non-orphaned via the standard {{include page="…"}} link mechanism, and then invoke the delete endpoint to execute arbitrary SQL inside the wiki database - including time-based blind data exfiltration from any table. This issue has been patched in version 4.6.6.

YesWiki, a PHP-based wiki system, contains a SQL injection vulnerability in the ApiController::deletePage() method affecting versions 4.2.0 through 4.6.5. The vulnerability arises from unsanitized interpolation of a page tag into a raw SQL DELETE query. An attacker with low-privilege authenticated access can create a page with a maliciously crafted tag containing SQL fragments, make the page non-orphaned using the include mechanism, and then invoke the delete API endpoint to execute arbitrary SQL. This allows time-based blind SQL injection enabling data exfiltration from any table in the wiki database. The attack vector is the POST /api/pages/{tag} endpoint which accepts arbitrary URL-encoded values including single quotes. The issue has been fully patched in YesWiki version 4.6.6 via proper input escaping.