How severe is CVE-2021-23167?

CVE-2021-23167 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability low.

Is CVE-2021-23167 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23167?

CVE-2021-23167 affects Gallagher Command Centre. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23167?

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

When was CVE-2021-23167 published?

CVE-2021-23167 was published on 2021-11-18 and last updated on 2026-06-17.

CVE-2021-23167

CVE-2021-23167 is a high-severity vulnerability in Gallagher Command Centre with a CVSS 3.x base score of 8.1. 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-295.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 4.3
EPSS exploit prediction: 0% (30th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Gallagher Command Centre
Published: 2021-11-18
Last modified: 2026-06-17

Description

Improper certificate validation vulnerability in SMTP Client allows man-in-the-middle attack to retrieve sensitive information from the Command Centre Server. This issue affects: Gallagher Command Centre 8.50 versions prior to 8.50.2048 (MR3); 8.40 versions prior to 8.40.2063 (MR4); 8.30 versions prior to 8.30.1454 (MR4) ; version 8.20 and prior versions.

Frequently asked questions

What is CVE-2021-23167?: Improper certificate validation vulnerability in SMTP Client allows man-in-the-middle attack to retrieve sensitive information from the Command Centre Server. This issue affects: Gallagher Command Centre 8.50 versions prior to 8.50.2048 (MR3); 8.40 versions prior to 8.40.2063 (MR4); 8.30 versions prior to 8.30.1454 (MR4) ; version 8.20 and prior versions.
How severe is CVE-2021-23167?: CVE-2021-23167 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability low.
Is CVE-2021-23167 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23167?: CVE-2021-23167 affects Gallagher Command Centre. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23167?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-23167 published?: CVE-2021-23167 was published on 2021-11-18 and last updated on 2026-06-17.

References

https://security.gallagher.com/Security-Advisories/CVE-2021-23167

Affected products (1)

cpe:2.3:a:gallagher:command_centre:*:*:*:*:*:*:*:*

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