{"id":"CVE-2026-52840","summary":"Easy!Appointments has server-side request forgery in CalDAV connection test that exposes the deployment's internal network","details":"Easy!Appointments is a self hosted appointment scheduler. In versions prior to 1.6.0, `Caldav::connect_to_server` at `application/controllers/Caldav.php:60` hands the request's `caldav_url` to a Guzzle `REPORT` call without scheme or host validation. A logged-in backend user (admin, provider, or secretary) reaches loopback, RFC1918, and link-local hosts on the deployment's network. The Guzzle exception path returns the upstream status code plus ~120 bytes of response body in the JSON `message` field (`Caldav.php:74-78`), so the SSRF is semi-blind. Version 1.6.0 contains a patch.","aliases":["GHSA-pm5p-7w5h-jm5q"],"modified":"2026-07-17T03:41:49.397689825Z","published":"2026-07-14T15:23:59.992Z","database_specific":{"cwe_ids":["CWE-918"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52840.json","cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52840.json"},{"type":"ADVISORY","url":"https://github.com/alextselegidis/easyappointments/security/advisories/GHSA-pm5p-7w5h-jm5q"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-52840"},{"type":"FIX","url":"https://github.com/alextselegidis/easyappointments/commit/6eb9336a91cfb276379506625e81f5bd9ed3a536"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/alextselegidis/easyappointments","events":[{"introduced":"0"},{"fixed":"6eb9336a91cfb276379506625e81f5bd9ed3a536"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"0"},{"fixed":"1.6.0"}]}}],"versions":["1.6.0-beta.2","1.6.0-beta.1","1.6.0-alpha.1","1.5.2-beta.1","1.5.1","1.5.1-beta.1","1.5.0","1.5.0-beta.1","1.5.0-alpha.1","1.5.0-dev.4","1.5.0-dev.3","1.5.0-dev.2","1.5.0-dev.1","1.3.0-beta.2","1.3.0-beta.1","1.3.0-alpha.1","1.2.0-beta.1","1.2.0-alpha.1","1.1.0","1.1.0-beta.2"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-52840.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N"}]}