CVE-2026-113349

MEDIUM 4.3

OpenCATS before 0.10.0 Missing Authorization in Calendar editEvent/deleteEvent

CVSS Score

4.3

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-639
Vendor	opencats
Product	opencats
Published	Oct 20, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

None

Affected Versions

opencats / OpenCATS

0 < 0.10.0

References

NVD ↗ CVE.org ↗ EPSS Data ↗

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

Credits

lighthousekeeper1212 🔍 leediay153 from Viettel Post