CVE-2023-38999Public exploitNetwork attack vector

Firewall shutdown via state-changing GET request

Published Aug 9, 2023 · Updated Oct 10, 2024

CSRF in OPNsense before Community Edition 23.7 and Business Edition 23.4.2 allows remote attackers to shut down the firewall. The SystemController haltAction accepted a state-changing GET request without requiring POST-only CSRF protection, then invoked the backend system halt command. Exploitation requires an administrator with an active management session to visit attacker-controlled content, and success powers off the instance.

CVSS severity6.5
Medium
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

CSRF in OPNsense before Community Edition 23.7 and Business Edition 23.4.2 allows remote attackers to shut down the firewall. The SystemController haltAction accepted a state-changing GET request without requiring POST-only CSRF protection, then invoked the backend system halt command. Exploitation requires an administrator with an active management session to visit attacker-controlled content, and success powers off the instance.

The record

CVE
CVE-2023-38999
Published
Aug 9, 2023
Updated
Oct 10, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-352, T1529
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 9, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 10, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-352Cross-Site Request Forgery (CSRF)
T1529System Shutdown/Reboot

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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