YesWiki before 4.6.7 Unauthenticated Page Overwrite via Bazar id_fiche

YesWiki before 4.6.7 contains an access control vulnerability allowing unauthenticated attackers to overwrite any existing wiki page, including pages whose write ACL restricts editing, via the Bazar entry-creation flow. Attackers can submit a crafted entry with an attacker-controlled id_fiche matching an existing page, overwriting its body for mass defacement and content destruction.