How severe is CVE-2023-39004?

CVE-2023-39004 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-39004 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-39004?

CVE-2023-39004 affects Opnsense. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-39004?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2023-39004 published?

CVE-2023-39004 was published on 2023-08-09 and last updated on 2026-07-05.

CVE-2023-39004

CVE-2023-39004 is a critical-severity vulnerability in Opnsense with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-732.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-732
Affected product: Opnsense
Published: 2023-08-09
Last modified: 2026-07-05

Description

Insecure permissions in the configuration directory (/conf/) of OPNsense Community Edition before 23.7 and Business Edition before 23.4.2 allow attackers to access sensitive information (e.g., hashed root password) which could lead to privilege escalation.

Frequently asked questions

What is CVE-2023-39004?: Insecure permissions in the configuration directory (/conf/) of OPNsense Community Edition before 23.7 and Business Edition before 23.4.2 allow attackers to access sensitive information (e.g., hashed root password) which could lead to privilege escalation.
How severe is CVE-2023-39004?: CVE-2023-39004 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-39004 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-39004?: CVE-2023-39004 affects Opnsense. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-39004?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-39004 published?: CVE-2023-39004 was published on 2023-08-09 and last updated on 2026-07-05.

References

Affected products (1)

cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:*

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