CVE-2026-108865

high

Description

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.

References

https://www.vulncheck.com/advisories/amoylab-unla-through-0.10.0-oauth2-authentication-bypass-via-authorize

https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/amoylab-unla-oauth-self-issued-token-authz

https://github.com/AmoyLab/Unla/blob/v0.10.0/internal/core/server.go#L229-L261

https://github.com/AmoyLab/Unla/blob/v0.10.0/internal/auth/oauth.go#L86-L147

https://github.com/AmoyLab/Unla

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-97016

Details

Source: Mitre, NVD

Published: 2026-10-11

Updated: 2026-10-11

Risk Information

CVSS v2

Base Score: 8.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:P/A:N

Severity: High

CVSS v3

Base Score: 8.2

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

Severity: High

CVSS v4

Base Score: 8.8

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

Severity: High