CVE-2026-90474
MCPHub before 1.0.32 contains an authentication bypass vulnerability in its embedded OAuth 2.0 authorization server where client authentication is disabled by default and PKCE enforcement is optional.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unscored. Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
MCPHub before 1.0.32 contains an authentication bypass vulnerability in its embedded OAuth 2.0 authorization server where client authentication is disabled by default and PKCE enforcement is optional. Attackers who obtain an authorization code through interception can redeem it for access tokens without providing a client secret or PKCE verifier, gaining access to victim accounts and their privileges.
- CVSS 4.0
- 7.6 HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- No score yet
- CISA KEV
- Not listed
- Weakness
- CWE-287
- Source
- disclosure@vulncheck.com
References
- https://github.com/samanhappy/mcphub/blob/v1.0.31/src/services/oauthServerService.ts#L26-L38
- https://github.com/samanhappy/mcphub/commit/e927620cd1a80e8691213b01eb8cd6ffa1a66e9f
- https://github.com/samanhappy/mcphub/releases/tag/v1.0.32
- https://github.com/samanhappy/mcphub/security/advisories/GHSA-3m7m-37xf-xp9x
- https://www.vulncheck.com/advisories/mcphub-before-1.0.32-oauth-2.0-authentication-bypass
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.