CVE Tools
Sign in

CVE-2026-31835

Vaultwarden WebAuthn credential metadata tampered before signature verification

Published: May 5, 2026Updated: May 11, 2026 Sources: CVE List NVDCWE-345
NVD MITRE
5.4CVSSMEDIUM
EPSS Score
0.2%
Top 95.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

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 Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:NI:LA:L
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:LIntegrity
Low
A:LAvailability
Low
Open in CVSS calculator →

Weaknesses

CWE-345

Affected Products

vaultwardendani-garcia
On-prem
Security Products / identity-access-mgmt
dani-garciaoss-projectSecurity Productsaka vaultwarden

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-x7g7-cgx5-jhx2
github.com
https://github.com/dani-garcia/vaultwarden/releases/tag/1.35.5
github.com

Timeline

Published
May 5, 2026
Last Updated
May 11, 2026

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2026-31835 and every CVE in our database. Create a free account — no credit card required.

Create Free Account
Plain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows