CVE-2026-54360: A mass assignment vulnerability exists in MISP’s sharing group creation endpoint. When creating a new sharing group, the controller did not remove a u...

Description

A mass assignment vulnerability exists in MISP’s sharing group creation endpoint. When creating a new sharing group, the controller did not remove a user-supplied id field before saving the submitted data. In CakePHP, supplying a primary key in the save data can cause a create() followed by save() operation to update an existing record instead of creating a new one. An authenticated user with permission to add sharing groups could therefore submit the identifier of an existing sharing group and modify that sharing group without passing the normal edit access-control checks. This may allow the attacker to take over or alter sharing groups they do not otherwise have access to, potentially affecting the confidentiality and integrity of information shared through those groups. Affected component: app/Controller/SharingGroupsController.php, add() action

Metrics

CVSS 4.0

8.4/10

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N/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

EPSS Probability

0.23%

13.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-639

References

https://github.com/MISP/MISP/commit/687e7cb530ae0e2faaadf5e3e44712258fb3ef1b

Timeline

Published: Jun 12, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-54360?

A mass assignment vulnerability exists in MISP’s sharing group creation endpoint. When creating a new sharing group, the controller did not remove a user-supplied id field before saving the submitted data. In CakePHP, supplying a primary key in the save data can cause a create() followed by save() operation to update an existing record instead of creating a new one. An authenticated user with permission to add sharing groups could therefore submit the identifier of an existing sharing group and modify that sharing group without passing the normal edit access-control checks. This may allow the attacker to take over or alter sharing groups they do not otherwise have access to, potentially affecting the confidentiality and integrity of information shared through those groups. Affected component: app/Controller/SharingGroupsController.php, add() action

How severe is CVE-2026-54360?

CVE-2026-54360 has a CVSS score of 8.4/10 (HIGH severity). The EPSS model estimates a 0.23% probability of exploitation in the next 30 days.

How do I fix CVE-2026-54360?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.