Vulnerability · Published Jun 4, 2026 · Assigned by CIRCL
CVE-2026-10855MISP Event template importer authorization bypass
Medium 5.1
In plain English
A medium-severity missing authorization in misp from misp. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities).
Official description
An authorization flaw existed in the MISP Event Template Importer overwrite workflow. When importing an event template in overwrite mode, the application checked whether a matching template already existed but did not verify that the importing user belonged to the organization that owned the existing template. As a result, an authenticated user with access to the template import functionality could forcibly overwrite an event template owned by another organization. Successful exploitation could allow unauthorized modification of another organization’s event template, potentially altering template structure, attributes, or metadata used for subsequent event creation or sharing workflows. Site administrators are not affected by this restriction, as they are explicitly allowed to overwrite templates across organizations. The issue was fixed by enforcing an ownership check before overwrite: non-site-admin users may only overwrite templates owned by their own organization.
Affected products (as reported)
Weakness: CWE-862 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N