Description
Seeyon Zhiyuan OA Web Application System versions up to and including 7.0 SP1 improperly decode and parse the `enc` parameter in thirdpartyController.do. The decoded map values can influence session attributes without sufficient authentication/authorization checks, enabling attackers to assign a session to arbitrary user IDs. VulnCheck has observed this vulnerability being exploited in the wild as of 2025-10-30 at 00:30:40.855917 UTC.
Problem types
CWE-306 Missing Authentication for Critical Function
Product status
Any version
Credits
Anonymous User via WeChat
References
github.com/...4853f3bfdf0a384/pocs/seeyon-oa-cookie-leak.yml
mp.weixin.qq.com/s/0AqdfTrZUVrwTMbKEKresg
github.com/...4853f3bfdf0a384/pocs/seeyon-oa-cookie-leak.yml
github.com/...fa8c0/http/misconfiguration/seeyon-unauth.yaml
www.vulncheck.com/...pplication-system-authentication-bypass