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CVE-2026-43911

Status: AnalyzedHigh (8.1)—

Vaultwarden is a Bitwarden-compatible server written in Rust. Prior to 1.35.5, refresh tokens are not invalidated when the user's security_stamp is rotated by some security-sensitive operations (password change, KDF change, key rotation, email change, org admin password reset, emergency access takeover). This allows an attacker holding a previously obtained refresh token to maintain session access even after the user has taken action to secure their account. This vulnerability is fixed in 1.35.5.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Atacante remoto autenticado (PR:L) explota gestión deficiente de tokens de actualización (CWE-613) para mantener acceso con credenciales previas tras cambios de seguridad. Permite reutilización de sesiones (T1078.004) y acceso con tokens válidos (T1550.001).

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Privileged Account ManagementAccount Use PoliciesApplication Developer GuidanceActive Directory ConfigurationVulnerability ScanningUser Training

Affected technologies (1)

Dani-garcia — Vaultwarden

CWEs

References

Raw JSON (NVD)

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  "id": "CVE-2026-43911",
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