CVE-2026-48548Network attack vector

Unintended command execution via missing CSRF cookie

Published Aug 26, 2026 · Updated Aug 26, 2026

Cross-site request forgery in Nagios Core before 4.5.12 allows remote attackers to execute arbitrary Nagios commands through a malicious POST. In cmd.cgi, the CSRF check treats an absent NagFormId cookie as valid, allowing the request to reach command execution without token comparison. The victim must be authenticated to the CGI interface and visit attacker-controlled content; commands execute with that user's Nagios authorization.

CVSS severity6.9
Medium
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site request forgery in Nagios Core before 4.5.12 allows remote attackers to execute arbitrary Nagios commands through a malicious POST. In cmd.cgi, the CSRF check treats an absent NagFormId cookie as valid, allowing the request to reach command execution without token comparison. The victim must be authenticated to the CGI interface and visit attacker-controlled content; commands execute with that user's Nagios authorization.

The record

CVE
CVE-2026-48548
Published
Aug 26, 2026
Updated
Aug 26, 2026
Vendor
Nagios Enterprises, LLC
Product
Nagios Core
Classifications
CWE-352, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 26, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <4.5.12

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Nagios Enterprises, LLC · Nagios Coreversion=0 <4.5.12

Published CVSS scores

6.9VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

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.

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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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-352Cross-Site Request Forgery (CSRF)
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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