How severe is CVE-2023-27100?

CVE-2023-27100 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-2023-27100 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-27100?

CVE-2023-27100 primarily affects Netgate Pfsense Plus. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-27100?

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-2023-27100 published?

CVE-2023-27100 was published on 2023-03-22 and last updated on 2026-06-17.

CVE-2023-27100

CVE-2023-27100 is a critical-severity vulnerability in Netgate Pfsense Plus 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-307.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 10% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Netgate Pfsense Plus
Published: 2023-03-22
Last modified: 2026-06-17

Description

Improper restriction of excessive authentication attempts in the SSHGuard component of Netgate pfSense Plus software v22.05.1 and pfSense CE software v2.6.0 allows attackers to bypass brute force protection mechanisms via crafted web requests.

Frequently asked questions

What is CVE-2023-27100?: Improper restriction of excessive authentication attempts in the SSHGuard component of Netgate pfSense Plus software v22.05.1 and pfSense CE software v2.6.0 allows attackers to bypass brute force protection mechanisms via crafted web requests.
How severe is CVE-2023-27100?: CVE-2023-27100 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-2023-27100 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-27100?: CVE-2023-27100 primarily affects Netgate Pfsense Plus. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-27100?: 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-2023-27100 published?: CVE-2023-27100 was published on 2023-03-22 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:netgate:pfsense_plus:22.05.1:*:*:*:*:*:*:*
cpe:2.3:a:pfsense:pfsense:2.6.0:*:*:*:community:*:*:*

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