Vulnerability · Published Oct 16, 2026 · Assigned by VulnCheck
CVE-2026-111633ZKEACMS through 4.4 Authentication Bypass via Hard-Coded JWT Signing Key
High 8.6
In plain English
A high-severity security flaw in ZKEACMS from SeriaWei. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities).
Severity (CVSS 3.1)8.6High
Exploit odds (30 days)0.4%top 61.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
ZKEACMS through 4.4 contains an authentication bypass vulnerability that allows unauthenticated attackers to forge REST API JWT bearer tokens using a hard-coded HMAC-SHA256 signing key in JwtBearerDefaults.cs. Attackers can sign a token with the Name claim set to 'admin' to call ApiAuthorize endpoints, modifying articles and products and reading form submissions.
Affected products (as reported)
Weakness: CWE-321 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L
References
- https://hackmd.io/@hieuPenguinnn/zkeacms-hardcoded-jwt-signing-key-admin-auth-bypass third-party-advisory
- https://github.com/SeriaWei/ZKEACMS/blob/v4.4/src/ZKEACMS/Api/JwtBearerDefaults.cs#L14-L19 technical-description
- https://github.com/SeriaWei/ZKEACMS/blob/v4.4/src/ZKEACMS/BuilderAuthentication.cs#L41-L52 technical-description
- https://github.com/SeriaWei/ZKEACMS/issues/531 issue-tracking
- VulnCheck Advisory: ZKEACMS through 4.4 Authentication Bypass via Hard-Coded JWT Signing Key third-party-advisory