Auth bypass in Opencats
CVE-2026-113349
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.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/opencats/OpenCATS/issues/720 (issue-tracking)
- github.com/opencats/OpenCATS/commit/aa3b414c3672f5010ca26c44192aa8e72d3735bd (patch)
- github.com/opencats/OpenCATS/releases/tag/v0.10.0 (release-notes)
- github.com/opencats/OpenCATS/blob/5781f41814f09493c7ce05b9251b5e09c1aff0cd/modu… (technical-description)
- github.com/opencats/OpenCATS/blob/5781f41814f09493c7ce05b9251b5e09c1aff0cd/modu… (technical-description)
- github.com/opencats/OpenCATS/blob/5781f41814f09493c7ce05b9251b5e09c1aff0cd/lib/… (technical-description)
- www.vulncheck.com/advisories/opencats-before-0.10.0-missing-authorization-in-ca… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-113349?
- CVE-2026-113349 is a medium-severity vulnerability in Opencats, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2026-10-20.
- How severe is CVE-2026-113349?
- Medium severity. CVSS v3 base score is 4.3 out of 10.