MISP Sharing Group Quick-Edit Actions Allow CSRF via State-Changing GET Requests

published 2026-09-04 2 mo ago modified 2026-09-10 59 d ago also EUVD-2026-70981

cvss: 8.6; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 10%
public exploits: 0; none known

MISP contains a cross-site request forgery (CSRF) vulnerability in the sharing group quick-edit functionality. The addOrg, removeOrg, addServer, and removeServer actions share the __initialiseSGQuickEdit() helper, where the HTTP method validation intended to restrict these operations to POST requests was commented out.

As a result, these state-changing actions could be invoked using GET requests. An attacker could craft a URL targeting one of the affected actions and cause an authenticated MISP user with sufficient privileges to request it, for example through a malicious link or embedded web resource.

Successful exploitation could modify the membership of a MISP sharing group without the victim intentionally performing the operation. Depending on the action performed, an attacker could add or remove organisations or servers from a sharing group, potentially granting unintended access to information distributed through that sharing group or disrupting legitimate information sharing.

The patch restores HTTP method enforcement centrally in __initialiseSGQuickEdit() by calling allowMethod(['post']), ensuring that all four affected quick-edit operations require POST requests and are therefore subject to the application's normal protections for state-changing requests.

Patch / fix

links 1

github.com/MISP/MISP@3060d93 commit

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 2 mo ago (2026-09-04)

Exploit prediction

0.21% chance of exploitation in the next 30 days, higher than 10% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.6	CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:L/SC:N/SI:L/SA:N
CNA	4.0	8.6	CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:L/SC:N/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

Affected products

misp misp

Classification

Weakness

CWE-352 Cross-Site Request Forgery

References

github.com /MISP/MISP/commit/3060d93cb
patch

Sources

CVE List CVE-2026-85546
NVD CVE-2026-85546

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary