CVE-2026-52840Public exploitNetwork attack vector

Authenticated internal-service disclosure via unchecked CalDAV URL

Published Jul 14, 2026 · Updated Jul 14, 2026

Server-side request forgery in Easy!Appointments before 1.6.0 allows remote authenticated users to probe internal services via CalDAV URLs. Caldav::connect_to_server passes the request's caldav_url unchanged to a Guzzle REPORT call, without validating the scheme, host, or resolved address. A backend account as an admin, provider, or secretary is required; exception messages expose upstream status, a short response fragment, or connection errors.

CVSS severity2.7
Low
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Server-side request forgery in Easy!Appointments before 1.6.0 allows remote authenticated users to probe internal services via CalDAV URLs. Caldav::connect_to_server passes the request's caldav_url unchanged to a Guzzle REPORT call, without validating the scheme, host, or resolved address. A backend account as an admin, provider, or secretary is required; exception messages expose upstream status, a short response fragment, or connection errors.

The record

CVE
CVE-2026-52840
Published
Jul 14, 2026
Updated
Jul 14, 2026
Vendor
Easy Appointments
Product
Easy Appointments
Classifications
CWE-918, T1046
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 14, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.6.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Easy Appointments · Easy Appointmentsversion=< 1.6.0

Published CVSS scores

2.7GitHubCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
T1046Network Service Discovery

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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