What’s Vulnerable › Vulnerabilities

CVE-2026-52840: Easy!Appointments has server-side request forgery in CalDAV connection test that exposes the deployment's internal network

• Severity: low (CVSS 2.7 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-14 · updated 2026-10-24
• Weakness: CWE-918

Description

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.

Affected products

• alextselegidis/easyappointments: before 1.6.0

References

• https://github.com/alextselegidis/easyappointments/commit/6eb9336a91cfb276379506625e81f5bd9ed3a536
• https://github.com/alextselegidis/easyappointments/security/advisories/GHSA-pm5p-7w5h-jm5q
• https://github.com/alextselegidis/easyappointments/security/advisories/GHSA-pm5p-7w5h-jm5q

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