CVE-2021-25297

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/switch/switch.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.

CVSS: 8.8Highscored by CISA
Exploited in the wild: Yes, in CISA KEV since 18 Jan 2022CISA deadline for US federal agencies: 1 Feb 2022public exploit code
EPSS: 56.7%chance of exploitation in the next 30 daystop 1% of scored CVEsFIRST score of 11 Nov 2026
Fix: Not stated by the vendorno fixed release in the CVE record
Published: 15 Feb 2021analysed here 12 Nov 2026

Do first. Apply updates per vendor instructions. (CISA's required action for this KEV entry)

Summary

Triage

Attack surface: Server-side
Exploitable: At runtime
Attack vector: network
Weakness: CWE-78 OS Command Injection
Can a WAF block it?: Partly. See why

The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.

Affected products

Products named in our analysis

nagios:nagios_xi

Fix and mitigation

WAF and other mitigations

Can a WAF block it? Partly. OS command injection puts shell syntax into the request. WAF rules catch common shell commands but miss encoded or unusual payloads.

Also consider: shlex/execve-style APIs

Based on the weakness type only; no CVE-specific evidence yet. We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.

Remediation steps (AI-written)

Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.

Exploitation evidence

CISA KEV catalog: Listed since 18 Jan 2022.
CISA due date: 1 Feb 2022, the remediation deadline for US federal agencies
CISA required action: Apply updates per vendor instructions.
Public exploit code: Yes: 1 Metasploit module · 1 Nuclei template
CISA SSVC: exploitation active, automatable no, technical impact totalAssessed by CISA 4 Feb 2025 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.

Metasploit

exploit/linux/http/nagios_xi_configwizards_authenticated_rceexploit, rank excellent

Nuclei

Nagios 5.5.6-5.7.5 - Authenticated Remote Command Injectiondetection template, high

Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.

Timeline

15 Feb 2021Published
18 Jan 2022Added to CISA KEV (exploited in the wild)336 days (about 11 months) later
1 Feb 2022CISA remediation due date (US federal agencies)14 days later
4 Feb 2025CISA SSVC assessment: exploitation active1,100 days (about 3 years) later
9 Jul 2026CVE record last updated519 days (about 1 year) later
12 Nov 2026Analysed by vulneraibility.com127 days (about 4 months) later

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Metric	Value	What it means
Attack vector	NetworkReachable over the internet or any routable network.	Reachable over the internet or any routable network.
Attack complexity	LowRepeatable attack, no special conditions.	Repeatable attack, no special conditions.
Privileges required	LowThe attacker needs basic user privileges.	The attacker needs basic user privileges.
User interaction	NoneNo victim action needed.	No victim action needed.
Scope	UnchangedImpact stays within the vulnerable component.	Impact stays within the vulnerable component.
Confidentiality	HighTotal data disclosure possible.	Total data disclosure possible.
Integrity	HighComplete modification possible.	Complete modification possible.
Availability	HighFull outage possible.	Full outage possible.

Common questions

Is CVE-2021-25297 being exploited?

Yes. CVE-2021-25297 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.

How severe is CVE-2021-25297?

CVE-2021-25297 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.

Is there a patch for CVE-2021-25297?

Not known from our data. No patch reference has been recorded for CVE-2021-25297, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.

What does CVE-2021-25297 affect?

CVE-2021-25297 affects nagios:nagios_xi. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.

Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.

References

NVD CVE.org CVE Details Source

6 references in the CVE record, grouped by the tags the record gives them.

Where the data on this page comes from

CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
NVD: CVSS and CPE data
CISA KEV catalog: exploitation, date added, due date
CISA Vulnrichment (ADP): SSVC decision points
FIRST EPSS: exploit probability and percentile
Metasploit Framework: exploit and scanner modules
Nuclei templates: detection templates

Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.

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