Auth bypass in Azukaar Cosmos-Server

CVE-2026-49446

Cosmos provides users the ability self-host a home server by acting as a secure gateway to your application, as well as a server manager. Prior to 0.22.19, tokenMiddleware in src/proxy/routerGen.go can return through the Constellation tunnel bypass before removing x-cosmos-user, x-cosmos-role, x-cosmos-user-role, and x-cosmos-mfa headers and before invoking AdminOnlyWithRedirect. An attacker with a valid x-cstln-auth API key for an enrolled device who reaches Cosmos through the Constellation Nebula tunnel can supply a chosen x-cosmos-user value to a route with AuthEnabled enabled when the upstream application trusts that forward-auth header. The request can bypass Cosmos JWT, password, MFA, and AdminOnly checks, allowing user impersonation and admin-tier reads or writes exposed by the proxied application. This issue is fixed in version 0.22.19.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-49446?
CVE-2026-49446 is a medium-severity vulnerability in Azukaar Cosmos-Server, classified under Improper Authorization. CVSS score: 6.1/10. Published 2026-09-15.
How severe is CVE-2026-49446?
Medium severity. CVSS v3 base score is 6.1 out of 10.