azukaar Cosmos Server up to 0.22.18 Token Middleware src/proxy/routerGen.go tokenMiddleware x-cosmos-user improper authentication

Summaryinfo

A vulnerability categorized as critical has been discovered in azukaar Cosmos Server up to 0.22.18. This affects the function tokenMiddleware of the file src/proxy/routerGen.go of the component Token Middleware. Such manipulation of the argument x-cosmos-user leads to improper authentication. This vulnerability is listed as CVE-2026-49446. The attack may be performed from remote. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in azukaar Cosmos Server up to 0.22.18 and classified as critical. Affected by this issue is the function tokenMiddleware of the file src/proxy/routerGen.go of the component Token Middleware. The manipulation of the argument x-cosmos-user with an unknown input leads to a improper authentication vulnerability. Using CWE to declare the problem leads to CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-49446 since 05/30/2026. The exploitation is known to be easy. The attack may be launched remotely. Technical details are known, but there is no available exploit.

Upgrading to version 0.22.19 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

• azukaar

Name

• Cosmos Server

Version

• 0.22.0
• 0.22.1
• 0.22.2
• 0.22.3
• 0.22.4
• 0.22.5
• 0.22.6
• 0.22.7
• 0.22.8
• 0.22.9
• 0.22.10
• 0.22.11
• 0.22.12
• 0.22.13
• 0.22.14
• 0.22.15
• 0.22.16
• 0.22.17
• 0.22.18

CPE 2.3info

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CPE 2.2info

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Entryinfo

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