{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-40566","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-04-14T13:24:29.474Z","datePublished":"2026-04-21T16:04:35.587Z","dateUpdated":"2026-04-21T17:33:11.528Z"},"containers":{"cna":{"title":"FreeScout vulnerable to SSRF via IMAP/SMTP Connection Test Endpoints","problemTypes":[{"descriptions":[{"cweId":"CWE-918","lang":"en","description":"CWE-918: Server-Side Request Forgery (SSRF)","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":4.1,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"NONE","privilegesRequired":"HIGH","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:N/A:N","version":"3.1"}}],"references":[{"name":"https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-fg98-rgx6-8x4g","tags":["x_refsource_CONFIRM"],"url":"https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-fg98-rgx6-8x4g"},{"name":"https://github.com/freescout-help-desk/freescout/commit/efe82e31b4a0d4c0b20025d09df0615e8139ff08","tags":["x_refsource_MISC"],"url":"https://github.com/freescout-help-desk/freescout/commit/efe82e31b4a0d4c0b20025d09df0615e8139ff08"},{"name":"https://github.com/freescout-help-desk/freescout/releases/tag/1.8.213","tags":["x_refsource_MISC"],"url":"https://github.com/freescout-help-desk/freescout/releases/tag/1.8.213"}],"affected":[{"vendor":"freescout-help-desk","product":"freescout","versions":[{"version":"< 1.8.213","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-04-21T16:04:35.587Z"},"descriptions":[{"lang":"en","value":"FreeScout is a free self-hosted help desk and shared mailbox. Versions prior to 1.8.213 have a Server-Side Request Forgery (SSRF) vulnerability in the IMAP/SMTP connection test functionality of FreeScout's `MailboxesController`. Three AJAX actions  `fetch_test` (line 731), `send_test` (line 682), and `imap_folders` (line 773) in `app/Http/Controllers/MailboxesController.php`  pass admin-configured `in_server`/`in_port` and `out_server`/`out_port` values directly to `fsockopen()` via `Helper::checkPort()` and to IMAP/SMTP client connections with zero SSRF protection. There is no IP validation, no hostname restriction, no blocklist of internal ranges, and no call to the project's own `sanitizeRemoteUrl()` or `checkUrlIpAndHost()` functions. The validation block in `connectionIncomingSave()` is entirely commented out. An authenticated admin can configure a mailbox's IMAP or SMTP server to point at any internal host and port, then trigger a connection test. The server opens raw TCP connections (via `fsockopen()`) and protocol-level connections (via IMAP client or SMTP transport) to the attacker-specified target. The response differentiates open from closed ports, enabling internal network port scanning. When the IMAP client connects to a non-IMAP service, the target's service banner or error response is captured in the IMAP debug log and returned in the AJAX response's `log` field, making this a semi-blind SSRF that enables service fingerprinting. In cloud environments, the metadata endpoint at `169[.]254[.]169[.]254` can be probed and partial response data may be leaked through protocol error messages. This is distinct from the `sanitizeRemoteUrl()` redirect bypass (freescout-3) -- different code path, different root cause, different protocol layer. Version 1.8.213 patches the vulnerability."}],"source":{"advisory":"GHSA-fg98-rgx6-8x4g","discovery":"UNKNOWN"}},"adp":[{"references":[{"url":"https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-fg98-rgx6-8x4g","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-21T17:33:06.910770Z","id":"CVE-2026-40566","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":"2026-04-21T17:33:11.528Z"}}]}}