CRLF Injection Vulnerability in Netgate pfSense CE
CVE-2026-111227

5.1MEDIUM

Key Information:

Vendor

Netgate

Status
Pfsense Ce
Vendor
CVE Published:
15 October 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-111227?

Netgate pfSense CE versions up to 2.9.0 are vulnerable to a CRLF injection flaw, which impacts the services_unbound_acls.php file. Authenticated users with the 'DNS Resolver: Access Lists' privilege can exploit this vulnerability. By injecting carriage return and line feed (CR/LF) characters into the aclname or aclaction fields, attackers can manipulate the access_lists.conf file. This enables them to introduce local data or zones and potentially alter DNS responses for clients on the local area network.

Affected Version(s)

pfSense CE 0 <= 2.9.0

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-2026-111227 - Proof of Concept

References

https://github.com/abraxas/pfsense-unbound-acl-crlf
exploittechnical-description
https://abraxaslabs.tech/research/pfsense-ce-leftovers
technical-description
https://github.com/pfsense/pfsense/blob/9363ac5b8651a1c7a...
technical-description

CVSS V4

Score:
5.1
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
Low
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

Abraxas Labs
.