CVE-2026-31835

Vaultwarden is a Bitwarden-compatible server written in Rust. In versions 1.35.4 and earlier, the WebAuthn authentication flow in `validate_webauthn_login()` updates persistent credential metadata (1backup_eligible1 and 1backup_state flags1) based on unverified `authenticatorData` before signature validation is performed. An attacker who knows a user's password but cannot produce a valid WebAuthn signature can permanently modify the stored backup flags for that user's credential. If signature verification fails, the database update is not rolled back. This can result in a persistent denial of service of WebAuthn two-factor authentication for affected credentials. This issue has been fixed in version 1.35.5.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/dani-garcia/vaultwarden/releases/tag/1.35.5	Product Release Notes
https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-x7g7-cgx5-jhx2	Exploit Vendor Advisory
https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-x7g7-cgx5-jhx2	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:dani-garcia:vaultwarden:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-05 19:16

Updated : 2026-07-25 11:10

NVD link : CVE-2026-31835

Mitre link : CVE-2026-31835

CVE.ORG link : CVE-2026-31835

JSON object : View

Products Affected

dani-garcia

vaultwarden

CWE

CWE-345

Insufficient Verification of Data Authenticity

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