Description (CNA)
YesWiki is a wiki system written in PHP. From version 4.6.2 to before version 4.6.6, HttpSignatureService::verifySignature() checks the result of PHP's openssl_verify() with a loose boolean negation - if (!openssl_verify(...)) { throw ... }. PHP's openssl_verify has four possible return values: 1, 0, -1, and "false". The -1 row is the bypass: PHP's truthiness rules make -1 a truthy value, so !(-1) === false, the throw is skipped, and the controller proceeds to processActivity(). Any condition that makes OpenSSL's EVP_VerifyFinal() return -1 triggers the bypass. The reachable consequence is the controller silently treats a failed verification as success and processes the attacker's payload. This issue has been patched in version 4.6.6.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| YesWiki / yeswiki | affected >= 4.6.2, < 4.6.6 |
CWE
CWE-347
References
- https://github.com/YesWiki/yeswiki/security/advisories/GHSA-mv28-wj57-f57g
- https://github.com/YesWiki/yeswiki/commit/d1795e0301e1a1078f17b4b98f56fff70de2029e
- https://github.com/YesWiki/yeswiki/releases/tag/v4.6.6
ADP enrichment
No English description supplied.