{"id":"CVE-2026-40591","state":"PUBLISHED","title":"FreeScout: Improper Authorization in Phone Conversation Creation Enables Cross-Mailbox Hidden Customer Modification","description":"FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, the phone-conversation creation flow accepts attacker-controlled `customer_id`, `name`, `to_email`, and `phone` values and resolves the target customer in the backend without enforcing mailbox-scoped customer visibility. As a result, a low-privileged agent who can create a phone conversation in Mailbox A can bind the new Mailbox A phone conversation to a hidden customer from Mailbox B and add a new alias email to that hidden customer record by supplying `to_email`. Version 1.8.214 fixes the vulnerability.","publishedAt":"2026-04-21T16:54:14.113Z","updatedAt":"2026-04-21T17:46:38.202Z","severity":{"score":7.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["freescout-help-desk freescout"],"affected":[{"vendor":"freescout-help-desk","product":"freescout","versions":[{"version":"< 1.8.214","status":"affected"}]}],"references":["https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-9ff4-mmhv-x6jp","https://github.com/freescout-help-desk/freescout/commit/83eea1ca47d97c6cdc90c501734bc2579b014a34","https://github.com/freescout-help-desk/freescout/releases/tag/1.8.214"],"weaknesses":["CWE-639"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/40xxx/CVE-2026-40591.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-40591","state":"PUBLISHED","datePublished":"2026-04-21T16:54:14.113Z","dateUpdated":"2026-04-21T17:46:38.202Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-14T14:07:59.641Z"},"containers":{"cna":{"title":"FreeScout: Improper Authorization in Phone Conversation Creation Enables Cross-Mailbox Hidden Customer Modification","descriptions":[{"lang":"en","value":"FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, the phone-conversation creation flow accepts attacker-controlled `customer_id`, `name`, `to_email`, and `phone` values and resolves the target customer in the backend without enforcing mailbox-scoped customer visibility. As a result, a low-privileged agent who can create a phone conversation in Mailbox A can bind the new Mailbox A phone conversation to a hidden customer from Mailbox B and add a new alias email to that hidden customer record by supplying `to_email`. Version 1.8.214 fixes the vulnerability."}],"affected":[{"vendor":"freescout-help-desk","product":"freescout","versions":[{"version":"< 1.8.214","status":"affected"}]}],"references":[{"url":"https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-9ff4-mmhv-x6jp","name":"https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-9ff4-mmhv-x6jp","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/freescout-help-desk/freescout/commit/83eea1ca47d97c6cdc90c501734bc2579b014a34","name":"https://github.com/freescout-help-desk/freescout/commit/83eea1ca47d97c6cdc90c501734bc2579b014a34","tags":["x_refsource_MISC"]},{"url":"https://github.com/freescout-help-desk/freescout/releases/tag/1.8.214","name":"https://github.com/freescout-help-desk/freescout/releases/tag/1.8.214","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":7.1,"baseSeverity":"HIGH","confidentialityImpact":"LOW","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N","version":"3.1"}}],"problemTypes":[{"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":"2026-04-21T16:54:14.113Z"},"source":{"advisory":"GHSA-9ff4-mmhv-x6jp","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-9ff4-mmhv-x6jp","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-21T17:46:34.226416Z","id":"CVE-2026-40591","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-21T17:46:38.202Z"}}]}}}