{"id":"CVE-2026-18639","state":"PUBLISHED","title":"Velociraptor OIDC Authenticator susceptible to email spoofing","description":"When Velociraptor is configured to use an OIDC IdP for authentication, it uses the email claim as a username. However, some IdP allow users to change the email claim without verification. Some IdPs do not set the \"email_verified\" claim and do not actually verify the email.\n\nThis allows a user to impersonate another user by setting their email address within the IdP, allowing account takeover.","publishedAt":"2026-08-11T15:05:42.703Z","updatedAt":"2026-08-11T17:14:12.967Z","severity":{"score":7.3,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N","source":"rapid7"},"assigner":"rapid7","products":["Rapid7 Velociraptor"],"affected":[{"vendor":"Rapid7","product":"Velociraptor","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"0.77.2","versionType":"semver"}],"repo":"https://github.com/Velocidex/velociraptor/"}],"references":["http://docs.velociraptor.app/announcements/advisories/cve-2026-18639/"],"weaknesses":["CWE-290"],"ingestedAt":"2026-10-29T20:11:10.572Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/18xxx/CVE-2026-18639.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-18639","state":"PUBLISHED","datePublished":"2026-08-11T15:05:42.703Z","dateUpdated":"2026-08-11T17:14:12.967Z","assignerShortName":"rapid7","assignerOrgId":"9974b330-7714-4307-a722-5648477acda7","dateReserved":"2026-08-03T10:45:09.071Z"},"containers":{"cna":{"title":"Velociraptor OIDC Authenticator susceptible to email spoofing","descriptions":[{"lang":"en","value":"When Velociraptor is configured to use an OIDC IdP for authentication, it uses the email claim as a username. However, some IdP allow users to change the email claim without verification. Some IdPs do not set the \"email_verified\" claim and do not actually verify the email.\n\nThis allows a user to impersonate another user by setting their email address within the IdP, allowing account takeover."}],"affected":[{"vendor":"Rapid7","product":"Velociraptor","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"0.77.2","versionType":"semver"}],"repo":"https://github.com/Velocidex/velociraptor/"}],"references":[{"url":"http://docs.velociraptor.app/announcements/advisories/cve-2026-18639/"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"REQUIRED","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"NONE","baseSeverity":"HIGH","baseScore":7.3,"vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-290","lang":"en","description":"CWE-290 Authentication bypass by spoofing","type":"CWE"}]}],"providerMetadata":{"shortName":"rapid7","orgId":"9974b330-7714-4307-a722-5648477acda7","dateUpdated":"2026-08-11T15:05:42.703Z"},"impacts":[{"capecId":"CAPEC-22","descriptions":[{"lang":"en","value":"CAPEC-22 Exploiting Trust in Client"}]}],"configurations":[{"lang":"en","value":"Velociraptor must be configured to use an IdP which does not verify a user's email and allows the user to set their email. Examples include Azure IdP and Keycloak in self enrollment mode.","supportingMedia":[{"type":"text/html","base64":false,"value":"Velociraptor must be configured to use an IdP which does not verify a user's email and allows the user to set their email. Examples include Azure IdP and Keycloak in self enrollment mode."}]}],"workarounds":[{"lang":"en","value":"You can change the claim that Velociraptor uses as the username using the  Configuration File https://docs.velociraptor.app/docs/deployment/references/#GUI.authenticator.claims.username  . Set the username using a more permanent claim for example with Azure the \"upn\" or \"oid\" can not be chosen by the user.","supportingMedia":[{"type":"text/html","base64":false,"value":"You can change the claim that Velociraptor uses as the username using the&nbsp;<a href=\"https://docs.velociraptor.app/docs/deployment/references/#GUI.authenticator.claims.username\">Configuration File</a>&nbsp;. Set the username using a more permanent claim for example with Azure the \"upn\" or \"oid\" can not be chosen by the user."}]}],"credits":[{"lang":"en","value":"Leonardo Souza (anauaque)","type":"finder"}],"source":{"discovery":"UNKNOWN"},"x_generator":{"engine":"Vulnogram 1.0.4"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-11T17:13:54.338948Z","id":"CVE-2026-18639","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-11T17:14:12.967Z"}}]}}}