CVE-2026-108865

AmoyLab Unla through 0.10.0 contains an authentication bypass vulnerability that allows unauthenticated attackers to obtain valid access tokens because the OAuth2 server never authenticates a resource owner. Attackers can register a client, request a code from /authorize, and exchange it at /token to access OAuth2-protected MCP prefixes, proxied upstream APIs and injected credentials.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/AmoyLab/Unla
https://github.com/AmoyLab/Unla/blob/v0.10.0/internal/auth/oauth.go#L86-L147
https://github.com/AmoyLab/Unla/blob/v0.10.0/internal/core/server.go#L229-L261
https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/amoylab-unla-oauth-self-issued-token-authz
https://www.vulncheck.com/advisories/amoylab-unla-through-0.10.0-oauth2-authentication-bypass-via-authorize

Configurations

No configuration.

History

11 Oct 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-11 14:17

Updated : 2026-10-16 19:18

NVD link : CVE-2026-108865

Mitre link : CVE-2026-108865

CVE.ORG link : CVE-2026-108865

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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