CVE-2026-52771

YesWiki from 4.6.2 before 4.7.0 contains a missing authorization vulnerability in ActivityPubService::syncActorPosts that lets malicious ActivityPub servers manipulate other actors' mirrored entries. Attackers can serve a poisoned outbox with cross-actor Delete, Update, or Create activities during admin-initiated sync.

YesWiki before 4.7.0 contains a cross-site request forgery vulnerability in the despam action (tools/security/actions/despam.php) that lets unauthenticated attackers delete or restore pages through an administrator's session. Attackers can plant an auto-submitting raw HTML form on a wiki page, so an administrator who views it posts parameters that delete PagePrincipale, configuration pages, or overwrite current content.

Missing authorization in the attachment download handler in YesWiki before 4.6.7 allows unauthenticated attackers to bypass page read ACLs. They can retrieve confidential attachments from read-restricted pages by knowing the page tag and file parameter.

Unrestricted file upload in YesWiki before 4.6.7 allows authenticated admins to write remote files into the web-accessible files/ directory via Bazar CSV import preview. They can import a CSV whose file or image field references a remote .php URL, which is saved without extension checks and executed as server-side code.

YesWiki before 4.6.7 contains an insufficient session expiration vulnerability because password reset tokens lack expiry timestamps. An attacker who obtains an unused reset URL from mailboxes, logs, backups, or browser history can submit a new password through checkEmailKey() and take over accounts.

YesWiki before 4.6.7 contains an authorization bypass vulnerability in ApiService::isAuthorized() that allows unauthenticated attackers to call admin-only API routes when public API mode is enabled. Attackers can send requests to endpoints like api/ci/update_config and api/archives to overwrite configuration and list, download, or delete backup archives.

YesWiki before 4.6.7 contains a stored cross-site scripting vulnerability in formatters/wakka.php. Users who can edit pages or post comments can inject event handlers by placing quotes in markdown image URLs, leading to JavaScript execution in viewers' browsers, including administrators.

YesWiki before 4.6.7 contains a server-side request forgery vulnerability that allows unauthenticated attackers to make server-side GET requests by supplying an unvalidated actor URL to the Bazar abonnements sync action. Attackers can target internal hosts or cloud metadata endpoints and chain attacker-controlled outbox first/next links, with fetched responses stored as readable Bazar entries.

YesWiki before 4.6.7 contains a server-side request forgery vulnerability that allows unauthenticated attackers to trigger server requests by sending signed Follow activities to the public forms actor inbox route. Attackers sign requests with their own keyId while supplying internal actor URLs in the body, reaching internal hosts or cloud metadata via blind GET and POST requests.

YesWiki before 4.6.7 contains an SQL injection vulnerability in the Bazar nuagetag action, which concatenates the unescaped tags attribute into a raw SQL IN clause. Attackers with page-write access (unauthenticated on default installs) can embed a nuagetag tag ending in a backslash to break quote parity and inject a UNION subquery, exfiltrating password hashes and arbitrary table data.