Smart License UtilityApplication · Cisco
CVE-2024-20439
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 vulnerability in Cisco Smart Licensing Utility (CSLU) could allow an unauthenticated, remote attacker to log into an affected system by using a static administrative credential. This vulnerability is due to an undocumented static user credential for an administrative account. An attacker could exploit this vulnerability by using the static credentials to login to the affected system. A successful exploit could allow the attacker to login to the affected system with administrative rights over the CSLU application API.
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 confidenceCisco Smart Licensing Utility (CSLU) contains an undocumented static administrative credential that allows unauthenticated remote attackers to gain administrative access to the CSLU application API. This hardcoded credential bypasses normal authentication mechanisms.
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
Smart License UtilityApplication
>= 2.0.0, < 2.3.0CVSS 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
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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 Cisco Smart Licensing Utility is installedLocate the CSLU installation on the system. On Windows, check Program Files for 'Cisco Smart Licensing Utility' folder or look for the cslu.exe process in Task Manager. On Linux, check common application directories or run 'ps aux | grep cslu' to find running processes.Affected if CSLU software is present on the system
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Identify the installed CSLU versionOpen the CSLU application and navigate to Help > About, or check the version displayed in the GUI. If accessing via API, the version information may be available in the application interface or installation logs.Affected if The version is 2.0.0, 2.1.x, or 2.2.x (any version >= 2.0.0 but < 2.3.0)
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Determine if CSLU API service is running and accessibleCheck if CSLU is listening on network ports. Run 'netstat -an | findstr LISTENING' or 'ss -tlnp' to identify ports where CSLU is bound. The CSLU API typically uses port 8443 or similar. Verify if the service is bound to 0.0.0.0 (all interfaces) rather than localhost only.Affected if The CSLU API service is running and bound to a network-accessible IP address
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Assess network exposure of the CSLU interfaceReview firewall rules, ACLs, or network segmentation around the CSLU host. Determine whether the CSLU management interface is reachable from untrusted networks or the internet. Check if external access to the CSLU port is permitted.Affected if The CSLU interface is accessible from networks outside the trusted administrative zone
You are affected if Cisco Smart Licensing Utility version 2.0.0 through 2.2.x is installed and its API interface is network-accessible to untrusted parties.
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 · scoped2.3.0
Apply Cisco's official patch when available; immediately disable or change the static credential if identified in documentation; restrict network access to CSLU interfaces until remediation.
Cisco Smart Licensing Utility version 2.3.0 or later
- Identify the current version of Cisco Smart Licensing Utility running on the system
- Download Cisco Smart Licensing Utility version 2.3.0 or later from the Cisco Software Download center (software.cisco.com) or obtain from official Cisco distribution channels
- Stop the CSLU service before upgrading
- Install the updated version (2.3.0 or later) following standard Cisco installation procedures
- Restart the CSLU service after installation
- Verify the new version is running by checking the CSLU interface or documentation
- Confirm the static credential vulnerability is remediated by verifying the undocumented account no longer functions
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Smart License Utility
Exploited in the wild — priority engagement
- Consultation4.0 h
- Implementation8.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,120.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2024-20439 — 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-2024-20439 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
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