CVE-2025-71402

better-auth versions greater than 1.3.34 and before 1.4.0 contain a vulnerability in the multi-session plugin's /sign-out after-hook, which trusts raw multi-session cookies and forwards extracted values to internalAdapter.deleteSessions without verifying the cookie signature (e.g., via getSignedCookie). An attacker can supply a forged _multi-* cookie to trigger deletion of arbitrary session tokens.

CVSS

No CVSS.

References

Link	Resource
https://github.com/better-auth/better-auth/security/advisories/GHSA-wmjr-v86c-m9jj
https://www.vulncheck.com/advisories/better-auth-before-session-revocation-via-forged-cookie

Configurations

No configuration.

History

29 Sep 2026, 14:10

Type	Values Removed	Values Added
Summary		(es) Las versiones de better-auth superiores a 1.3.34 y anteriores a 1.4.0 contienen una vulnerabilidad en el after-hook /sign-out del plugin de multi-sesión, que confía en las cookies de multi-sesión sin procesar y reenvía los valores extraídos a internalAdapter.deleteSessions sin verificar la firma de la cookie (p. ej., a través de getSignedCookie). Un atacante puede proporcionar una cookie _multi-* falsificada para activar la eliminación de tokens de sesión arbitrarios.

Information

Published : 2026-08-01 13:16

Updated : 2026-10-06 22:10

NVD link : CVE-2025-71402

Mitre link : CVE-2025-71402

CVE.ORG link : CVE-2025-71402

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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