by Kastro
Paper/Archive/CVE-2021-4461

CVE-2021-4461

Seeyon Zhiyuan OA Web Application System — Seeyon Zhiyuan OA Web Application System < 7.0 SP1 Authentication Bypass

EPSS 0.5%CVSS 9.3
critical.is priorityof 100
36
CVSS 9.3 (CNA)9.3 / 10 × 3027.9Not in CISA KEV+300.0EPSS percentile 42.2.422 × 208.4No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
Zhiyuan OA Web Application System≤ 7.0 SP1–CNA

Scores by source

VulnCheck (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

exploitmp.weixin.qq.com/s/0AqdfTrZUVrwTMbKEKresgexploitgithub.com/chaitin/xray/blob/f90cf321bc4d294bbf6625a9c4853f3bfdf0a384/pocs/seeyon-oa-cookie-leak.ymlexploitgithub.com/projectdiscovery/nuclei-templates/blob/1ca6b8e6fe225cbd46dcb893dcaee01447afa8c0/http/misconfiguration/seeyon-unauth.yaml#L20writeupvulncheck.com/advisories/seeyon-zhiyuan-oa-web-application-system-authentication-bypass