OpenCATS before 0.10.0 contains a missing authorization vulnerability in CalendarUI::onEditEvent() and onDeleteEvent() that allows authenticated users to modify or delete other users' calendar events. Attackers with EDIT or DELETE access can supply arbitrary eventID values to alter or remove any user's events, including non-public ones restricted to their owner.

Metrics

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact Low

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact partial

Affected Vendors & Products

Vendors Products
Opencats
  • Opencats

No data.

No data.

References
Link Providers
https://github.com/opencats/OpenCATS/blob/5781f41814f09493c7ce05b9251b5e09c1aff0cd/lib/Calendar.php#L83-L150 cve-icon cve-icon
https://github.com/opencats/OpenCATS/blob/5781f41814f09493c7ce05b9251b5e09c1aff0cd/modules/calendar/CalendarUI.php#L555-L585 cve-icon cve-icon
https://github.com/opencats/OpenCATS/blob/5781f41814f09493c7ce05b9251b5e09c1aff0cd/modules/calendar/CalendarUI.php#L690-L712 cve-icon cve-icon
https://github.com/opencats/OpenCATS/commit/aa3b414c3672f5010ca26c44192aa8e72d3735bd cve-icon cve-icon
https://github.com/opencats/OpenCATS/issues/720 cve-icon cve-icon
https://github.com/opencats/OpenCATS/releases/tag/v0.10.0 cve-icon cve-icon
https://www.vulncheck.com/advisories/opencats-before-0.10.0-missing-authorization-in-calendar-editevent-deleteevent cve-icon cve-icon
History

Fri, 23 Oct 2026 00:45:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Tue, 20 Oct 2026 12:45:00 +0000

Type Values Removed Values Added
Description OpenCATS before 0.10.0 contains a missing authorization vulnerability in CalendarUI::onEditEvent() and onDeleteEvent() that allows authenticated users to modify or delete other users' calendar events. Attackers with EDIT or DELETE access can supply arbitrary eventID values to alter or remove any user's events, including non-public ones restricted to their owner.
Title OpenCATS before 0.10.0 Missing Authorization in Calendar editEvent/deleteEvent
First Time appeared Opencats
Opencats opencats
Weaknesses CWE-639
CPEs cpe:2.3:a:opencats:opencats:*:*:*:*:*:*:*:*
Vendors & Products Opencats
Opencats opencats
References
Metrics cvssV3_1

{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N'}

cvssV4_0

{'score': 5.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'}
cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-10-20T10:41:36.105Z

Updated: 2026-10-22T21:19:07.705Z

Reserved: 2026-10-20T01:07:44.982Z

Link: CVE-2026-113349

cve-icon Vulnrichment

Updated: 2026-10-22T21:19:03.188Z

cve-icon NVD

Status : Deferred

Published: 2026-10-20T11:17:19.010

Modified: 2026-10-22T22:18:02.977

Link: CVE-2026-113349

cve-icon Redhat

No data.