Cyber Resilience

CVE-2022-31814

RCE in Netgate Pfblockerng ≤ 2.1.4_26

Public PoCHigh EPSSRCECommand Injection
Published
05 September 2022
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.87 99.7th percentile
Risk Priority 97 floored blend · peak EPSS

Summary

CVE-2022-31814 is a critical-severity OS Command Injection (CWE-78) vulnerability in Netgate Pfblockerng. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 0.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and SI-2 (Flaw Remediation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2022-31814 is an OS command injection vulnerability, tracked as CWE-78, that affects the pfBlockerNG package in pfSense up through version 2.1.4_26. The flaw permits arbitrary operating-system command execution as root when specially crafted shell metacharacters are supplied in the HTTP Host header; version 3.x of the package is explicitly unaffected.

Unauthenticated remote attackers can exploit the issue over the network without any user interaction or credentials. Successful exploitation grants full root-level control of the affected pfSense system, enabling arbitrary command execution, persistence, or further lateral movement within the environment.

Public references point to a corrective commit merged via the FreeBSD-ports repository and advise users to upgrade pfBlockerNG to a fixed release or migrate to the unaffected 3.x branch. Netgate documentation for pfBlockerNG also directs administrators to apply available package updates through the pfSense interface.

The CVE maintains a very high EPSS score, with a recorded peak of 0.9710 and a current value of 0.9432, and public proof-of-concept exploits have been posted to PacketStorm, indicating active interest in the flaw after disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

pfSense pfBlockerNG through 2.1.4_26 allows remote attackers to execute arbitrary OS commands as root via shell metacharacters in the HTTP Host header. NOTE: 3.x is unaffected.

CWE(s)

Related Threats

Likely ATT&CK TechniquesAI

Techniques this vulnerability likely enables, inferred from its description, weakness type, and attributed-actor tradecraft. Confidence is per-technique.

T1190 Exploit Public-Facing Application Initial Accessconfidence: HIGH
Unauthenticated remote attackers can inject OS commands via the HTTP Host header, directly enabling exploitation of a public-facing application.
T1059 Command and Scripting Interpreter Executionconfidence: HIGH
The vulnerability allows arbitrary operating-system command execution as root through crafted shell metacharacters.
T1068 Exploitation for Privilege Escalation Privilege Escalationconfidence: HIGH
Successful exploitation grants full root-level control, directly facilitating privilege escalation to root.
T1543.003 Windows Service Persistenceconfidence: MEDIUM
Root access obtained via the injection can be used to create or modify Windows services for persistence.
T1053.005 Scheduled Task Executionconfidence: MEDIUM
Root privileges enable creation of scheduled tasks to maintain access after initial compromise.
inferred from description + CWE · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2023-27253Same vendor: Netgate
CVE-2023-48123Same vendor: Netgate
CVE-2019-16667Same vendor: Netgate
CVE-2016-20057Same vendor: Netgate
CVE-2024-57273Same vendor: Netgate
CVE-2024-46538Same vendor: Netgate
CVE-2023-42326Same vendor: Netgate
CVE-2016-20058Same vendor: Netgate
CVE-2024-54780Same vendor: Netgate
CVE-2023-42327Same vendor: Netgate

Affected Assets

netgate
pfblockerng
≤ 2.1.4_26

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-10 Information Input Validation
  • SI-2 Flaw Remediation
  • SC-7 Boundary Protection
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.2.5
  • V1.2.8
  • V15.2.5

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly requires validation and sanitization of untrusted HTTP Host header input to block shell metacharacters that enable OS command injection.

prevent

Mandates timely application of the pfBlockerNG package update or migration to the unaffected 3.x branch that eliminates the command-injection flaw.

prevent

Enforces boundary-protection rules that can restrict or deny unauthenticated network access to the pfSense web interface where the vulnerable Host-header processing occurs.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.

PR.PS-02 partial match
prevents

Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.

References