Missing Authentication in Stamparm Maltrail Blacklist Endpoint
CVE-2026-91002

6.9MEDIUM

Key Information:

Vendor

Stamparm

Status
Maltrail
Vendor
CVE Published:
15 September 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-91002?

A vulnerability has been detected in Stamparm Maltrail prior to version 3.1, specifically in the Blacklist Endpoint's _blacklist function located in core/httpd.py. This security flaw permits unauthorized users to manipulate the endpoint, leading to missed authentication checks. An attacker could exploit this vulnerability remotely, and public exploits are accessible. Immediate upgrading to version 3.1 is recommended, as it addresses the issue by requiring an authenticated session or by utilizing the new Blacklist_ALLOWLIST option, implementing vital security controls.

Affected Version(s)

maltrail 3.0.0

maltrail 3.0.1

maltrail 3.1

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-91002 - Proof of Concept

References

https://vuldb.com/vuln/403583
vdb-entrytechnical-description
https://vuldb.com/vuln/403583/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-91002
third-party-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

inmoyang (VulDB User)
VulDB CNA Team
.