Vulnerability record

CVE-2021-4461

A permanent, source-backed tracker page. Values are shown only when returned; explicit gaps and read failures remain different states.

Full record read. Reported values and explicit gaps below come from the tracked record. Tracker snapshot: Aug 8, 2026.

What it is

Reported

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. Source description excerpt; complete tracked detail loads below.

NVD published: Oct 31, 2025 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

What is affected

Reported

seeyon — zhiyuan_oa_web_application_system. Product-level identification only; no affected-version conclusion is available from this field.

NVD published: Oct 31, 2025 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Urgency and basis

Reported

Act · 446.9

Tracker decision tier from the evidence detailed below · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Exploitation evidence

Reported

kev-listed · VulnCheck KEV

VulnCheck KEV added: Oct 30, 2025 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

What to do

Reported

Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Tracked source remediation field · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Evidence detail

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