Quick answers
- Is CVE-2026-26477 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-26477 being exploited in the wild.
- How severe is CVE-2026-26477?
- Medium severity, with a CVSS score of 4.3, published 3 April 2026.
- Which products and versions are affected?
- DokuWiki 2025-05-14b "Librarian" [56.2].
- Is there a fix for CVE-2026-26477?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-26477 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-26477?
- Check whether you run DokuWiki at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
An unauthenticated denial of service (DoS) vulnerability exists in DokuWiki's media upload functionality within 'inc/media.php'. The 'media_upload_xhr()' function fails to validate the directory depth of the 'qqfile' parameter, which is used as a file identifier. Because DokuWiki interprets colons (:) as directory separators, an attacker can provide a filename containing a large number of colons (e.g., '123:123:...:123.pdf'). This forces the server to recursively create deeply nested directory structures, leading to CPU exhaustion and filesystem resource depletion. The attack can be performed remotely without authentication via a POST request to 'lib/exe/ajax.php'.
Affected products
- DokuWiki DokuWiki 2025-05-14b "Librarian" [56.2]
Timeline
- 2026-01-09: disclosed: Vulnerability details shared on GitHub by researcher Hebing123
- 2026-04-03: advisory: CVE published and initial CISA-ADP assessment provided