Vulnerability Report

CVE-2026-43911

Title: Vaultwarden Refresh Token Invalidation Bypass

Other

Proof Of Concept

No public PoC currently indexed for CVE-2026-43911.

CWE Category CWE-613

Published Date May 11, 2026

Modified Date May 18, 2026

Exploit Status Not Found

Score 6.8 CVSS v3.1

Exploit Probability (EPSS)

0.31%

Vulnerability Summary

CVE-2026-43911: 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.

Impacted Vendors

dani-garcia 1

Reference Links

https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-6j4w-g4jh-xjfx

CVSS v3.1

Source Entity [email protected]

Severity HIGH

8.1

Attack Vector

NETWORK

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

CVSS v3.1

Source Entity [email protected]

Severity MEDIUM

6.8

Attack Vector

NETWORK

Complexity

HIGH

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-43911 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

May 18, 2026 MODIFIED

Vulnerability data updated via NVD.

May 13, 2026 MODIFIED

Vulnerability data updated via NVD.

May 12, 2026 MODIFIED

Vulnerability data updated via NVD.

May 11, 2026 MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK

Complexity LOW

Privileges N/A

Interaction NONE

CVSS Vector String


                                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Affected Stack

No specific products linked.