CVE-20XX-?
agent?

CVE-2026-56423

9.4 CRITICAL 0.5% exploit odds Fix listed Auth & access

What it is

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.

At a glance

Exploitability
Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering, service disruption.
Exploit odds
0.5% chance of exploitation in the next 30 days (EPSS).
Fix
A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

  1. PublishedDisclosed publicly on CVE.org and NVD
  2. Last updatedMost recent change to the record

Why it ranks here

Details

Published
Last modified
Exploit probability
0.5% · EPSS, next 30 days
Weakness
CWE-862 · Missing authorization
Record status
Analyzed

Affected

Attack profile CVSS 4.0 · 9.4

Attack vector
Network
Complexity
Low
Attack requirements
None
Privileges needed
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Raw vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Is it in your code?

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Fix and advisories

References

NVD record · CVE.org record