How severe is CVE-2021-25298?

CVE-2021-25298 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-25298 being actively exploited?

Yes. CVE-2021-25298 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-01-18, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2021-25298?

CVE-2021-25298 affects Nagios Nagios Xi. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-25298?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2021-25298 have an EU (EUVD) identifier?

Yes. CVE-2021-25298 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-12198. It is also flagged as exploited in the EUVD (since 2022-01-18).

When was CVE-2021-25298 published?

CVE-2021-25298 was published on 2021-02-15 and last updated on 2026-07-06.

CVE-2021-25298

CVE-2021-25298 is a high-severity vulnerability in Nagios Nagios Xi with a CVSS 3.x base score of 8.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-01-18). The underlying weakness is classified as CWE-78.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 75% (99th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-01-18)
EU (EUVD) id: EUVD-2021-12198
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-01-18)
Weakness: CWE-78
Affected product: Nagios Nagios Xi
Published: 2021-02-15
Last modified: 2026-07-06

Description

Nagios XI version xi-5.7.5 is affected by OS command injection. The vulnerability exists in the file /usr/local/nagiosxi/html/includes/configwizards/cloud-vm/cloud-vm.inc.php due to improper sanitization of authenticated user-controlled input by a single HTTP request, which can lead to OS command injection on the Nagios XI server.

Frequently asked questions

What is CVE-2021-25298?: Nagios XI version xi-5.7.5 is affected by OS command injection. The vulnerability exists in the file /usr/local/nagiosxi/html/includes/configwizards/cloud-vm/cloud-vm.inc.php due to improper sanitization of authenticated user-controlled input by a single HTTP request, which can lead to OS command injection on the Nagios XI server.
How severe is CVE-2021-25298?: CVE-2021-25298 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-25298 being actively exploited?: Yes. CVE-2021-25298 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-01-18, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2021-25298?: CVE-2021-25298 affects Nagios Nagios Xi. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-25298?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2021-25298 have an EU (EUVD) identifier?: Yes. CVE-2021-25298 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-12198. It is also flagged as exploited in the EUVD (since 2022-01-18).
When was CVE-2021-25298 published?: CVE-2021-25298 was published on 2021-02-15 and last updated on 2026-07-06.

References

Affected products (1)

cpe:2.3:a:nagios:nagios_xi:*:*:*:*:*:*:*:*

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