CVE-2021-25296Known exploitationPublic exploitNetwork attack vector

Authenticated command execution via unescaped WMI argument

Published Feb 15, 2021 · Updated Jul 9, 2026

OS command injection in Nagios XI 5.5.6 through 5.7.5 allows remote authenticated users to execute commands through its Windows WMI wizard. The wizard appends the HTTP-supplied plugin_output_len value to three WMI command strings and passes them to PHP exec() without shell escaping. Non-administrator Nagios XI access is sufficient, and injected commands run as the Apache service account on the monitoring server.

CVSS severity8.8
High
EPSS probability72.18%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OS command injection in Nagios XI 5.5.6 through 5.7.5 allows remote authenticated users to execute commands through its Windows WMI wizard. The wizard appends the HTTP-supplied plugin_output_len value to three WMI command strings and passes them to PHP exec() without shell escaping. Non-administrator Nagios XI access is sufficient, and injected commands run as the Apache service account on the monitoring server.

The record

CVE
CVE-2021-25296
Published
Feb 15, 2021
Updated
Jul 9, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Mar 16, 2021Exploitation reportedUnit 42 observed cryptojacking exploitation
  3. Jan 18, 2022Exploitation reportedCISA Known Exploited Vulnerabilities Catalog listing
  4. Jul 9, 2026Record 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 privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
9.0NIST NVDAV:N/AC:L/Au:S/C:C/I:C/A:C

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesauthenticated
Known exploitationReported
Public exploitPublished

Weakness, pattern, technique

T1190Exploit Public-Facing Application

Public exploit references

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

Reported exploitation

Technologies

Your stack

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Your stack

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