CVE-2021-4461

CRITICAL 9.3CVE-2021-4461 · Published 30/10/2025 · updated 17/06/2026

In short

CVE-2021-4461 is a CRITICAL (CVSS 9.3) vulnerability.
Chance of exploitation in the next 30 days (EPSS): 0.49%, higher than 42.2% of all vulnerabilities.
No patched version is listed yet: follow the vendor's advisory in References.

Package	Affected versions	Patched versions
—	No affected product versions are listed for this vulnerability yet.

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.

References

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