CVE-2026-49446: Cosmos: Authentication bypass via forward-auth header smuggling on Constellation tunnel in Cosmos-Server
azukaar · Cosmos-Server
Affected: azukaar Cosmos-Server · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 22% of scored CVEs
DescriptionCVE.org
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.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- azukaar · Cosmos-Server< 0.22.19
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Published
- September 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-49446 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.