CVE-2026-103239

HIGH CVSS 4.0: 8.6 EPSS 0.35%
Updated Sep 30, 2026
Payload
Parameter Value
CVSS 8.6 (HIGH)
Type CWE-284 (Improper Access Control), CWE-862 (Missing Authorization)
Vendor Payload
Public PoC No

MISP contains a privilege escalation vulnerability in the tag collection creation and editing functionality. The affected actions accepted the full HTTP request payload and passed it to a bulk-association save operation, which writes not only the intended tag collection record but also any associated model data present in the payload. A user holding the tag editor permission could craft a request that includes additional model data (such as User or Organisation records) alongside the tag collection fields.

Because the save operation processed all associated models indiscriminately, the injected sibling records were written to the database, enabling the attacker to modify or create privileged accounts and escalate to site administrator. Preconditions: - An authenticated account with the tag editor permission (perm_tag_editor) - Network access to the MISP instance Impact: - Unauthorized creation or modification of User and Organisation records - Privilege escalation from tag editor to site administrator Affected versions: < 2.5.48

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
None
No disruption

CVSS Vector v4.0