CVE-2026-52839: 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

lowCVSS 3.3CVE-2026-52839

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.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: low — CVSS 3.3
Published: 2026-07-14
Last updated: 2026-07-15
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-52839

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-528390.15% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 4% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-52839	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

lowGHSA-w8xc-8g92-v77h: Easy!Appointments appointments/store and appointments/update allow cross-provider appoint…ghsa

Recent advisories for Easy!Appointments is a

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

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