CVE Catalog

CVE-2026-80218

HighCVSS 7.6
Published: Translated: NVD NIST

Summary

An improper authentication vulnerability in AshAuthentication allows an attacker with a sign-in token for one authenticated resource to be signed in as a user of a different resource. The issue arises from incorrect parsing of the sub claim in the JWT token.

Risk Assessment

An attacker could take over the identity of a user from another resource, leading to unauthorized access and breach of resource isolation.

Recommendation

Upgrade ash_authentication to version 4.15.0 or later (for 4.x) and 5.0.0-rc.14 or later (for 5.0.0-rc) with the fix. Ensure tokens are bound to the correct resource.

Other vulnerabilities in AshAuthentication

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Original NVD description (English source)

Improper Authentication vulnerability in team-alembic AshAuthentication allows an attacker holding a sign-in token for one authenticated resource to be signed in as a user of a different resource. AshAuthentication.Strategy.Password.SignInWithTokenPreparation.extract_primary_keys_from_subject/2 parses the JWT sub claim (for example user?id=1) with URI.parse/1 and keeps only its query string, discarding the path segment that names the subject the token was issued for. Nothing else restores that binding: AshAuthentication.Jwt.verify/3 checks the signature, exp, nbf, jti and the library-version claims, the purpose check only requires sign_in, and the remaining comparison is over primary-key field names, which are identical across resources. The WebAuthn sign-in and remember-me preparations carry copies of the same helper and drop the path in the same way. The magic link sign-in path pins the subject name against the resource and is not affected. This issue affects ash_authentication: from 3.10.5 before 4.15.0 and from 5.0.0-rc.0 before 5.0.0-rc.14.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS