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Fencer Intel
low 2.7

CVE-2026-52840 json

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

published 3mo ago modified yesterday also EUVD-2026-43722 , GHSA-pm5p-7w5h-jm5q

cvss
2.7
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 14%
public exploits
0
none known

Summary

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.

Patch / fix

  • packagist alextselegidis/easyappointments 1.6.1
  • easyappointments easyappointments 1.6.0

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
3mo ago

Exploit prediction

0.23% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/alextselegidis/easyappointments/security/advisories/GHSA-pm5p-7w5h-jm5q referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 2.7 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N
GitHub 3.1 2.7 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N

Affected packages

ecosystem package affected fixed in
packagist alextselegidis/easyappointments
<1.6.1
1.6.1

Affected products

  • alextselegidis easyappointments

Classification

Weakness
  • CWE-918 Server-Side Request Forgery

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.