CVE-2026-91857

MEDIUM CVSS 4.0: 5.3 EPSS 0.21%
Updated Sep 15, 2026
Misp
Parameter Value
CVSS 5.3 (MEDIUM)
Type CWE-352 (Cross-Site Request Forgery (CSRF))
Vendor Misp
Public PoC No

Affected versions of MISP expose several state-changing controller actions without restricting them to POST. The affected actions are:  - EventReportsController::purgeUnusedPictures()  - NoticelistsController::enableNoticelist()  - ServersController::removeOrphanedCorrelations()  - WorkflowsController::rebuildRedis() The patch adds allowMethod(['post']) to each action, preventing them from being triggered through ordinary GET requests. For purgeUnusedPictures(), the corresponding UI previously used $.get().

The fix converts that request to POST and supplies X-CSRF-Token, while the controller enables header-only CSRF validation for that AJAX action. Because GET requests can be induced cross-origin through links, images, redirects, or navigation, accepting GET for these state-changing operations can let an attacker trigger them using the authenticated victim's session. Version affected: ≤2.5.45

Attack Parameters

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

Impact Assessment

Confidentiality
None
No data leak
Integrity
Low
Partial data modification
Availability
Low
Partial disruption

CVSS Vector v4.0

Vulnerable Products

misp:misp