CVE-2026-25622
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 · uneditedA Captive Portal Custom Handler command injection vulnerability exists in Arista Edge Threat Management - Arista Next Generation Firewall (NGFW). On affected platforms, an administrative account logged into the user interface can exploit this input handling behavior to execute arbitrary platform shell commands.
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 · high confidenceA command injection vulnerability exists in the Captive Portal Custom Handler of Arista Edge Threat Management/NGFW. An authenticated administrative user with UI access can exploit improper input handling to execute arbitrary shell commands on the underlying platform.
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< 17.4.1CVSS 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
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- Low
- Availability
- Low
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:L/A:L
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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Identify Arista Ng Firewall versionAccess the administrative UI or use CLI to retrieve the system version. In the CLI, this is typically shown via 'show version' or accessible through the web interface under System > Status or About sections.Affected if The installed version is lower than 17.4.1
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Confirm Captive Portal feature is enabledNavigate to the web administrative UI and locate the Captive Portal settings, typically under Network > Captive Portal or Users > Captive Portal. Check if the feature is toggled to enabled.Affected if Captive Portal is enabled in the configuration
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Verify Custom Handler is configuredWithin the Captive Portal configuration panel, locate the Custom Handler field or section. Inspect whether any custom handler scripts or commands are defined.Affected if A Custom Handler is defined with custom command strings
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Inspect Custom Handler for injection vectorsReview the Custom Handler configuration for unsanitized input patterns, particularly looking for shell metacharacters (; | & $ ` or command substitution patterns) within command fields.Affected if The Custom Handler contains shell metacharacters or appears to concatenate user-supplied input into shell commands
You are affected if your Arista Ng Firewall version is below 17.4.1 AND the Captive Portal Custom Handler feature is enabled with a configured custom command that could accept or concatenate user input.
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.
dbcve · scoped17.4.1
Restrict administrative access to trusted users, implement strict input validation/sanitization on captive portal custom handler inputs, and apply vendor patches when available.
Ng Firewall 17.4.1
- Identify the current Arista Ng Firewall version in use
- Schedule a maintenance window for the upgrade process
- Back up the current configuration following standard backup procedures
- Upgrade to Ng Firewall version 17.4.1 or later
- Verify the upgrade completed successfully
- Confirm the Captive Portal Custom Handler functionality is working as expected
- Validate the configuration was preserved after upgrade
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation6.0 h
- Testing3.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-25622 — 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-2026-25622 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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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data