CVE-2026-104908 MISP Decaying Model Import Mass Assignment Allows Cross-Organization Model Overwrite and Default Flagging
Authenticated users can overwrite other organizations' decaying models and alter default flags due to improper input validation in the import endpoint.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-104908?
CVE-2026-104908 is a high-severity missing authorization vulnerability in MISP, published on 2 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
MISP contains an improper input validation vulnerability in the decaying model import functionality. The import endpoint was intended to create a new decaying model belonging exclusively to the importing user's organisation, with the default flag forced to off.
However, the application stripped only the top-level id and uuid fields and pinned org_id and default on the outer array before saving the data flat. A user with decaying-model permissions could supply a nested model key carrying its own primary key, organisation identifier, and default flag, which bypassed those guards during the save operation.
Impact:
- A user with perm_decaying could overwrite an existing decaying model belonging to another organisation in place, altering its name, formula, parameters, or ownership.
- A user could create or modify a model flagged as the organisation default, affecting scoring behaviour for other users.
- A user could reassign a model's organisation to an arbitrary value.
Preconditions:
- Authenticated user with decaying-model permission (perm_decaying).
- Network access to the MISP instance.
Affected: <2.5.48.
Which versions are affected by CVE-2026-104908?
How do I fix CVE-2026-104908?
No fix has been published for CVE-2026-104908 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-2026-104908 being exploited?
There is no known exploitation of CVE-2026-104908 in the wild and no public exploit code.
Sources
Also known as GHSA-h9vw-jjgr-29wc.