CVE-2025-2767
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedArista NG Firewall User-Agent Cross-Site Scripting Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Arista NG Firewall. Minimal user interaction is required to exploit this vulnerability. The specific flaw exists within the processing of the User-Agent HTTP header. The issue results from the lack of proper validation of user-supplied data, which can lead to the injection of an arbitrary script. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-24407.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceArista NG Firewall contains a stored XSS vulnerability in its User-Agent HTTP header processing logic. Due to insufficient input validation, an attacker can inject arbitrary JavaScript through the User-Agent header. This XSS can be chained to achieve remote code execution as root, likely because the web interface or associated processes run with elevated privileges. The attack requires minimal user interaction.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data= 17.1.1CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Confirm Arista NG Firewall is installedIdentify the product by checking system information, running processes, or checking the web interface login page for Arista NG Firewall brandingAffected if The system is not Arista NG Firewall
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Verify the installed version is 17.1.1Check the firewall's web interface version information typically found in System > Status or Help > About, or run CLI commands like 'sudo nfctl status' or check /var/log/ngfw/version if accessibleAffected if The version is 17.1.1 exactly
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Confirm the web management interface is exposedCheck if the HTTP/HTTPS management port (typically 443 or 9443) is listening and accessible from network perspectivesAffected if The web interface is reachable over the network
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Inspect HTTP access logs for unusual User-Agent patternsReview web server logs (typically in /var/log/nginx/ or /var/log/httpd/) for entries where the User-Agent header contains script tags, javascript:, or other XSS payloadsAffected if Log entries show XSS patterns in User-Agent values that were stored or reflected
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Check for unexpected root-level processes or reverse shellsUse commands like 'ps aux | grep root' or review running services to identify any suspicious processes spawned from the web interface user contextAffected if Unexpected processes are running that were not initiated by administrators
The environment is affected if it is Arista NG Firewall version 17.1.1 with the web management interface exposed to network traffic.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataImplement strict input validation and output encoding for the User-Agent header at the point of processing; apply vendor patch when available or consider WAF rules to block malicious User-Agent patterns as an interim control.
- Consultation6.0 h
- Implementation8.0 h
- Testing10.0 h
- Review / QA4.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2025-2767 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2025-2767 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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