CVE-2026-54397 MISP event editing allows unauthorized assignment to undisclosed sharing groups
Authenticated users can bypass authorization checks to assign events to unauthorized sharing groups, leading to information disclosure and metadata modification.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-54397?
CVE-2026-54397 is a medium-severity missing authorization vulnerability in misp, published on 12 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
A vulnerability in MISP’s non-REST event editing path allowed an authenticated user with event edit permissions to manipulate the submitted form data and set an event’s sharing_group_id to a sharing group they were not authorized to use. When distribution was set to sharing group distribution, the non-REST save path accepted the submitted sharing_group_id without performing the same sharing group authorization check enforced by the REST edit path.
An attacker could exploit this by tampering with the event edit request and assigning an event to an undisclosed or unauthorized sharing group. This could result in unauthorized use of restricted sharing groups, disclosure of the sharing group name in event listings, and unintended modification of the event’s distribution metadata.
The issue is fixed by validating that the selected sharing group can be used by the current user when the sharing group is changed, and by clearing sharing_group_id when the event distribution is not set to sharing group distribution.
Weakness: CWE-863
Which versions are affected by CVE-2026-54397?
How do I fix CVE-2026-54397?
No fix has been published for CVE-2026-54397 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-54397 being exploited?
There is no known exploitation of CVE-2026-54397 in the wild and no public exploit code.
Sources
Also known as GHSA-4qr4-pqwx-m352.