A cross-site request forgery (CSRF) vulnerability existed in the cullEmptyEvents action of MISP. The endpoint performed a state-changing and irreversible operation while accepting HTTP GET requests. Because bodyless GET requests are not subject to CakePHP's CSRF validation, an attacker could cause an authenticated MISP user with sufficient privileges to invoke the endpoint simply by causing their browser to load a crafted URL, for example through an embedded image or other automatically requested resource. Successful exploitation triggers the deletion of published empty events. The deletion is particularly significant because the operation uses skipBlocklist, meaning the removed events do not leave blocklist entries that could prevent or track their subsequent synchronization. This can result in unintended and potentially irreversible deletion of MISP event records without explicit user interaction. The vulnerability was addressed by restricting cullEmptyEvents to HTTP POST requests, ensuring that CakePHP's normal CSRF protections are applied to the operation.
History

Thu, 03 Sep 2026 17:00:00 +0000

Type Values Removed Values Added
First Time appeared Misp
Misp misp
Vendors & Products Misp
Misp misp

Thu, 03 Sep 2026 15:30:00 +0000

Type Values Removed Values Added
Description A cross-site request forgery (CSRF) vulnerability existed in the cullEmptyEvents action of MISP. The endpoint performed a state-changing and irreversible operation while accepting HTTP GET requests. Because bodyless GET requests are not subject to CakePHP's CSRF validation, an attacker could cause an authenticated MISP user with sufficient privileges to invoke the endpoint simply by causing their browser to load a crafted URL, for example through an embedded image or other automatically requested resource. Successful exploitation triggers the deletion of published empty events. The deletion is particularly significant because the operation uses skipBlocklist, meaning the removed events do not leave blocklist entries that could prevent or track their subsequent synchronization. This can result in unintended and potentially irreversible deletion of MISP event records without explicit user interaction. The vulnerability was addressed by restricting cullEmptyEvents to HTTP POST requests, ensuring that CakePHP's normal CSRF protections are applied to the operation.
Title MISP cullEmptyEvents CSRF Allows Irreversible Deletion of Events via GET Request
Weaknesses CWE-352
References
Metrics cvssV4_0

{'score': 8.8, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: CIRCL

Published:

Updated: 2026-09-03T15:13:00.493Z

Reserved: 2026-09-03T15:12:56.306Z

Link: CVE-2026-85236

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Undergoing Analysis

Published: 2026-09-03T16:18:27.013

Modified: 2026-09-03T16:45:08.223

Link: CVE-2026-85236

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-03T16:45:06Z