Vulnerability · Published Sep 21, 2026 · Assigned by CIRCL

CVE-2026-94383MISP Blocklist Workflow Module: Arbitrary Script Execution via Unrestricted File Extension

High 8.6

In plain English

A high-severity unrestricted file upload in MISP from MISP. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities).

Severity (CVSS 4.0)8.6High
Exploit odds (30 days)0.5%top 56.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

The MISP blocklist workflow module accepted a user-supplied blocklist filename parameter without validating the file extension. The only sanitization applied was basename() to strip path components and a check for empty or dot values. A site administrator could specify a filename with an arbitrary extension that would be placed in the MISP export directory. If the underlying web server is configured to interpret and execute scripts from that directory, the resulting file could be invoked, leading to arbitrary code execution in the context of the web server process. The vulnerability requires the attacker to hold site-administrator privileges within MISP, as the blocklist workflow module is restricted to that role. No additional user interaction is required beyond triggering the workflow action with a crafted filename parameter. The impact is full compromise of the MISP server's confidentiality, integrity, and availability, as arbitrary script execution grants the attacker the same privileges as the web server user. Version affected: <2.5.47

Affected products (as reported)

VendorProductVersions
MISP MISP 0 – before 2.5.47

Weakness: CWE-434, CWE-20 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References