VulnerabilityDeferred

CVE-2026-49446

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.

MEDIUM 6.1EPSS 0.30%

Does this matter?

Lower severity and a low EPSS score (0.30%). Track it; it rarely justifies an emergency change on its own.

Description

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 3.1: 6.1 MEDIUMCVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
EPSS: 0.30% probability · 22th percentile
Public exploits: None in Exploit-DB
CISA KEV: Not listed
Weakness: CWE-285, CWE-290
Source: security-advisories@github.com

EPSS trend

EPSS 0.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.