Vulnerability · Published Sep 30, 2026 · Assigned by CIRCL
CVE-2026-103235MISP Event Delegation Mass Assignment Allows Retargeting Delegation to Arbitrary Events
High 8.7
In plain English
A high-severity authorization bypass via user-controlled key 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 0.3% (higher than 20% of all known vulnerabilities).
Official description
MISP contains a mass assignment vulnerability in the event delegation feature. When a user with delegation permission submits a delegation request, the application authorized the user against the event identified in the URL but then persisted the entire submitted record, including caller-supplied fields such as the primary key and event_id. An authenticated attacker could inject a primary key or event_id into the delegation payload to retarget an existing delegation record to any event on the instance. Because a delegation row grants the requesting organisation read access to the event it references, this effectively granted read access to arbitrary events belonging to other organisations. If the target organisation subsequently accepted the delegation, ownership of the event was transferred and the original record was deleted. Preconditions: - An authenticated user with the delegation permission (perm_delegate) - The MISP.delegation server setting must be enabled Impact: - Confidentiality: read access to any event on the instance - Integrity: overwriting existing delegation records and transferring event ownership Affected versions: MISP < 2.5.48
Affected products (as reported)
Weakness: CWE-915, CWE-639 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N
References
- Security patch patch