CVE-2026-9349Public exploitNetwork attack vector

Unauthenticated booking-data disclosure via unchecked view parameters

Published May 24, 2026 · Updated May 24, 2026

Information disclosure in Cal.diy 4.9.0 through 4.9.4 allows remote attackers to read booking data via crafted booking-view requests. The booking view's getServerSideProps handler processes attacker-controlled cancelledBy and rescheduledBy values without adequate access control and returns server-rendered information. No authentication or user interaction is required; published sources do not identify the exact disclosed fields.

CVSS severity5.3
Medium
EPSS probability0.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Cal.diy 4.9.0 through 4.9.4 allows remote attackers to read booking data via crafted booking-view requests. The booking view's getServerSideProps handler processes attacker-controlled cancelledBy and rescheduledBy values without adequate access control and returns server-rendered information. No authentication or user interaction is required; published sources do not identify the exact disclosed fields.

The record

CVE
CVE-2026-9349
Published
May 24, 2026
Updated
May 24, 2026
Vendor
Cal.com, Inc.
Product
Cal.diy
Classifications
CWE-284, CWE-200
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 24, 2026CVE publishedPublication date reported by the CVE source.
  2. May 24, 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=4.9.0
  2. Affected versionversion=4.9.1
  3. Affected versionversion=4.9.2
  4. Affected versionversion=4.9.3
  5. Affected versionversion=4.9.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Cal.com, Inc. · Cal.diyversion=4.9.0; version=4.9.1; version=4.9.2; version=4.9.3; version=4.9.4

Published CVSS scores

5.0VulDBAV:N/AC:L/Au:N/C:P/I:N/A:N
5.3VulDBCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.5VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-284Improper Access Control
CWE-200Exposure of Sensitive Information to an Unauthorized Actor

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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