Quick answers
- Is CVE-2026-90474 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-90474 being exploited in the wild.
- How severe is CVE-2026-90474?
- Medium severity, with a CVSS score of 6.8, published 12 September 2026.
- Which products and versions are affected?
- Samanhappy Mcphub before 1.0.32.
- Is there a fix for CVE-2026-90474?
- A patch was published on 2026-08-23: Fix committed to repository Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-90474 attacked?
- It is attacked over the network, in a hosted service.
- Am I affected by CVE-2026-90474?
- Check whether you run Samanhappy Mcphub at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is an authentication bypass in MCPHub's embedded OAuth 2.0 authorization server. The root cause is that client authentication is disabled by default and PKCE (Proof Key for Code Exchange) enforcement is optional. An attacker who obtains an authorization code through network interception can exchange it for access tokens at the token endpoint without presenting a client secret or valid PKCE verifier. This affects the OAuth token exchange flow and requires only network access and code interception. The fix (version 1.0.32+) enforces mandatory client authentication for confidential clients and requires S256-only PKCE for public clients.
Affected products
- samanhappy MCPHub before 1.0.32
Timeline
- 2026-09-12: disclosed
- 2026-08-23: patched: Fix committed to repository