{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31835","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-03-09T17:41:56.078Z","datePublished":"2026-05-05T18:51:35.457Z","dateUpdated":"2026-05-06T12:46:11.308Z"},"containers":{"cna":{"title":"Vaultwarden WebAuthn credential metadata tampered before signature verification","problemTypes":[{"descriptions":[{"cweId":"CWE-345","lang":"en","description":"CWE-345: Insufficient Verification of Data Authenticity","type":"CWE"}]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"LOW","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":5.3,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","version":"4.0"}}],"references":[{"name":"https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-x7g7-cgx5-jhx2","tags":["x_refsource_CONFIRM"],"url":"https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-x7g7-cgx5-jhx2"},{"name":"https://github.com/dani-garcia/vaultwarden/releases/tag/1.35.5","tags":["x_refsource_MISC"],"url":"https://github.com/dani-garcia/vaultwarden/releases/tag/1.35.5"}],"affected":[{"vendor":"dani-garcia","product":"vaultwarden","versions":[{"version":"< 1.35.5","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-05-05T18:51:35.457Z"},"descriptions":[{"lang":"en","value":"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."}],"source":{"advisory":"GHSA-x7g7-cgx5-jhx2","discovery":"UNKNOWN"}},"adp":[{"references":[{"url":"https://github.com/dani-garcia/vaultwarden/security/advisories/GHSA-x7g7-cgx5-jhx2","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-06T12:45:50.889395Z","id":"CVE-2026-31835","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-05-06T12:46:11.308Z"}}]}}