SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-52839

A normal authenticated provider can inject new appointments into another provider's schedule via `store`, or reassign existing appointments into a foreign provider's calendar via `update`.

LOW 3.3EPSS 0.18%

Does this matter?

Lower severity and a low EPSS score (0.18%). Track it; it rarely justifies an emergency change on its own.

Description

Easy!Appointments is a self hosted appointment scheduler. Versions prior to 1.6.0 correctly filter provider-scoped appointments in the `appointments/search` response, proving that provider isolation is an intended security boundary. However, the direct mutation endpoints `appointments/store` and `appointments/update` only check generic appointment privileges and never verify that the submitted `id_users_provider` belongs to the current session. A normal authenticated provider can inject new appointments into another provider's schedule via `store`, or reassign existing appointments into a foreign provider's calendar via `update`. The `store` path contains an additional write-before-crash bug: the unauthorized row is committed to the database before the controller crashes on a type error, so the attacker receives an error response while the foreign appointment is already persisted. Version 1.6.0 patches the issue.

CVSS 3.1
3.3 LOWCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:N
EPSS
0.18% probability · 7th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-639, CWE-862
Source
security-advisories@github.com
EPSS trend
0%3%5%26 October 2026: 0.18%26 October 202626 October 2026

EPSS 0.2% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.