CVE-2024-20439
CriticalExploitedPublic exploitA 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.
Published Sep 5, 2024 · Updated Oct 21, 2025 · Also known as TR-24-1398
Key Facts
Patch immediately- CVE-2024-20439 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Smart License Utility (Cisco).
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Feb 27, 2025. Public exploit code is available.
- EPSS estimates a 97% probability of exploitation in the next 30 days.
- Fixed versions are available, including Smart License Utility 2.3.0.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
97%
Higher than 99.8% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2024-20439 brief as a PDF
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Description
A 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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Mar 31, 2025 | Apr 21, 2025 | Not reported |
| Industry KEV feed | Feb 27, 2025 | Apr 21, 2025 | Not reported |
| CIRCL KEV | Mar 31, 2025 | Apr 21, 2025 | Not reported |
| ENISA EUVD | Mar 31, 2025 | n/a | Not reported |
Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Affected Products
2 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Smart License UtilityCisco | >= 2.1.0 | 2.3.0 |
Patched Releases
Smart License Utility
2.3.0
Timeline
Publicly disclosed
Sep 5, 2024
Added to Industry KEV feed
Feb 27, 2025
Added to CISA KEV
Mar 31, 2025
Added to CIRCL KEV
Mar 31, 2025
Added to ENISA EUVD
Mar 31, 2025
Last updated
Oct 21, 2025
Weakness Type
- CWE-798 Use of Hard-coded Credentials
- CWE-912 Hidden Functionality
References
- advisorycisco-sa-cslu-7gHMzWmw
- advisoryhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-duo-epic-info-sdLv6h8y
- advisoryhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-expressway-auth-kdFrcZ2j
- advisoryhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-injection-6kn9tSxm
- advisoryUSOM advisory
FAQ
Common Questions.
A 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.
Affected: Smart License Utility (Cisco) versions >= 2.1.0. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Feb 27, 2025.
Yes. It was added on Mar 31, 2025 with a federal remediation due date of Apr 21, 2025.
Public exploit code is available.
Fixed versions are available, including Smart License Utility 2.3.0.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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