{"id":"CVE-2026-105639","state":"PUBLISHED","title":"Plane: Pre-auth workspace invitation hijack via email-squat and self-served invitation token leak in Plane","description":"Plane is an open-source project management tool. Prior to 1.4.0, Plane's signup flow creates a logged-in User row for any submitted email without an out-of-band ownership check, while User.email is unique=True. The authenticated user can call GET /api/users/me/workspaces/invitations/, which returns each WorkspaceMemberInvite whose email matches request.user.email. WorkSpaceMemberInviteSerializer uses fields = \"all\", exposing the token that protects the invitation join endpoint. An unauthenticated attacker who knows a target's email can register an account using that address, enumerate pending invitations, and accept an invitation as the target, joining a workspace at the invited role. The term pre-auth describes the attacker's initial state: the attacker has no credential before signup, while the enumeration and join requests use the session created by that signup. This issue is fixed in 1.4.0.","publishedAt":"2026-10-05T18:10:35.787Z","updatedAt":"2026-10-06T14:52:44.084Z","severity":{"score":9.8,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["makeplane plane"],"affected":[{"vendor":"makeplane","product":"plane","versions":[{"version":"< 1.4.0","status":"affected"}]}],"references":["https://github.com/makeplane/plane/security/advisories/GHSA-4vj8-p63v-8p24","https://github.com/makeplane/plane/pull/9297","https://github.com/makeplane/plane/commit/6220ba990b2276a1a1979d1d5df68f650b8b47ad","https://github.com/makeplane/plane/releases/tag/v1.4.0"],"weaknesses":["CWE-200","CWE-287","CWE-639"],"ingestedAt":"2026-10-29T20:10:23.711Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/105xxx/CVE-2026-105639.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-105639","state":"PUBLISHED","datePublished":"2026-10-05T18:10:35.787Z","dateUpdated":"2026-10-06T14:52:44.084Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-10-05T16:40:39.612Z"},"containers":{"cna":{"title":"Plane: Pre-auth workspace invitation hijack via email-squat and self-served invitation token leak in Plane","descriptions":[{"lang":"en","value":"Plane is an open-source project management tool. Prior to 1.4.0, Plane's signup flow creates a logged-in User row for any submitted email without an out-of-band ownership check, while User.email is unique=True. The authenticated user can call GET /api/users/me/workspaces/invitations/, which returns each WorkspaceMemberInvite whose email matches request.user.email. WorkSpaceMemberInviteSerializer uses fields = \"all\", exposing the token that protects the invitation join endpoint. An unauthenticated attacker who knows a target's email can register an account using that address, enumerate pending invitations, and accept an invitation as the target, joining a workspace at the invited role. The term pre-auth describes the attacker's initial state: the attacker has no credential before signup, while the enumeration and join requests use the session created by that signup. This issue is fixed in 1.4.0."}],"affected":[{"vendor":"makeplane","product":"plane","versions":[{"version":"< 1.4.0","status":"affected"}]}],"references":[{"url":"https://github.com/makeplane/plane/security/advisories/GHSA-4vj8-p63v-8p24","name":"https://github.com/makeplane/plane/security/advisories/GHSA-4vj8-p63v-8p24","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/makeplane/plane/pull/9297","name":"https://github.com/makeplane/plane/pull/9297","tags":["x_refsource_MISC"]},{"url":"https://github.com/makeplane/plane/commit/6220ba990b2276a1a1979d1d5df68f650b8b47ad","name":"https://github.com/makeplane/plane/commit/6220ba990b2276a1a1979d1d5df68f650b8b47ad","tags":["x_refsource_MISC"]},{"url":"https://github.com/makeplane/plane/releases/tag/v1.4.0","name":"https://github.com/makeplane/plane/releases/tag/v1.4.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":9.8,"baseSeverity":"CRITICAL","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-200","lang":"en","description":"CWE-200: Exposure of Sensitive Information to an Unauthorized Actor","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-287","lang":"en","description":"CWE-287: Improper Authentication","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-639","lang":"en","description":"CWE-639: Authorization Bypass Through User-Controlled Key","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-05T18:10:35.787Z"},"source":{"advisory":"GHSA-4vj8-p63v-8p24","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-06T14:37:11.181590Z","id":"CVE-2026-105639","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-06T14:52:44.084Z"}}]}}}