CVE-2026-56423
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk13th percentile - higher than 13% of all known CVEs
Summary
MISP Core contained broken access-control checks in the bulk deletion flows for Event Reports and Sharing Groups. Users with broad permissions could delete objects belonging to other organizations without proper authorization.
Risk Assessment
An authenticated attacker with relevant permissions could exploit these vulnerabilities to delete event report content or sharing group configurations, leading to data loss across the instance.
Recommendation
It is recommended to implement detailed authorization checks for each object before deletion to prevent unauthorized access to other organizations' data.
Original NVD description (English source)
MISP Core contained broken access-control checks in the bulk deletion flows for Event Reports and Sharing Groups. The affected deleteSelection handlers authorized deletion using broad role-level permissions instead of validating authorization for each selected object. For Event Reports, EventReportsController::deleteSelection relied on the global perm_add capability rather than a per-report ownership/authorization check. As a result, a contributor-level user could submit report IDs or UUIDs for reports belonging to other organisations and hard-delete them instance-wide. The fix changed the callback to call EventReport::fetchIfAuthorized($user, $itemId, 'delete') for each selected report before deletion. For Sharing Groups, SharingGroupsController::deleteSelection relied on the global perm_sharing_group capability rather than verifying ownership of each selected sharing group. This allowed a sharing-group-capable user to hard-delete sharing groups owned by other organisations, bypassing the per-object ownership gate used by the single-object delete action. The fix changed the callback to call SharingGroup::checkIfOwner($user, $itemId) for each selected sharing group. An authenticated attacker with the relevant broad role permission could abuse the affected bulk deletion endpoints to delete objects outside their organisation’s authorization scope, causing loss of event-report content or sharing-group configuration across the instance.