CVE-2024-20439: Technical Deep-Dive (Auto Refreshed)

Generated on 2026-03-24T18:22:55.243Z. This file is automatically regenerated every 30 minutes by the CVE AI enrichment job using web sources (NVD, MITRE, CISA KEV, GitHub).

Executive Technical Summary

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.

• Context preserved from previous revision: 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. Notes: Ostorlab KEV: One-command to detect most remotely known exploitable vulnerabilities. Sourced from CISA KEV, Google's Tsunami, Ostorlab's Asteroid and Bug Bounty programs.

Technical Details

• CVE: CVE-2024-20439
• KEV date added: 2025-03-31
• KEV due date: 2025-04-21
• NVD published: 2024-09-04
• NVD modified: 2025-10-28
• MITRE modified: 2025-10-21
• CVSS base score: 9.8
• CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
• CVSS exploitability score: 3.9
• CVSS impact score: 5.9
• Attack vector: Network
• Attack complexity: Low
• Privileges required: None
• User interaction: None
• Scope: Unchanged
• Confidentiality impact: High
• Integrity impact: High
• Availability impact: High

Versions and Products Impacted

• cisco / smart license utility (versions: >= 2.0.0, < 2.3.0)
• Cisco / Cisco Smart License Utility (versions: 2.1.0, 2.0.0, 2.2.0)
• cisco / cisco_smart_license_utility (versions: 2.1.0, 2.0.0, 2.2.0)

Weakness Classification

• CWE-912
• CWE-798

Repositories for Lab Validation (Public Examples)

• Ostorlab/KEV | stars: 608 | updated: 2026-03-23 | https://github.com/Ostorlab/KEV
  Notes: Ostorlab KEV: One-command to detect most remotely known exploitable vulnerabilities. Sourced from CISA KEV, Google's Tsunami, Ostorlab's Asteroid and Bug Bounty programs.
• tylzars/awesome-vrre-writeups | stars: 17 | updated: 2026-03-17 | https://github.com/tylzars/awesome-vrre-writeups
  Notes: A collection of Vulnerability Research and Reverse Engineering writeups.
• packetinside/CISA_BOT | stars: 0 | updated: 2025-08-08 | https://github.com/packetinside/CISA_BOT
  Notes: CISA Bot is a GitHub bot that automatically monitors the Cybersecurity and Infrastructure Security Agency (CISA) Known Exploited Vulnerabilities (KEV) Catalog. When new vulnerabilities are published in the KEV, the bot creates GitHub issues in this repository with detailed information about each vulnerability.

People and Organizations Mentioned

• cisco
• Smart Licensing Utility
• Ostorlab
• tylzars
• packetinside

Practical Defensive Validation (Authorized Only)

1. Use only isolated environments and systems you own or are explicitly authorized to test.
2. Snapshot infrastructure before validation and preserve baseline logs (EDR, SIEM, OS, app).
3. Inventory cisco / smart license utility (versions: >= 2.0.0, < 2.3.0) assets and confirm exact vulnerable versions with automated checks.
4. Patch in staged environments and validate closure with scanners + service health checks.
5. Map detections to MITRE ATT&CK tactics relevant to your environment and tune alert quality.

References

• NVD record: https://nvd.nist.gov/vuln/detail/CVE-2024-20439
• MITRE CVE record: https://www.cve.org/CVERecord?id=CVE-2024-20439
• CISA KEV Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
• CISA KEV JSON feed: https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json
• KEV notes: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cslu-7gHMzWmw ; https://nvd.nist.gov/vuln/detail/CVE-2024-20439
• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cslu-7gHMzWmw
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-20439
• Repository example: https://github.com/Ostorlab/KEV
• Repository example: https://github.com/tylzars/awesome-vrre-writeups
• Repository example: https://github.com/packetinside/CISA_BOT

This content is for defensive security training and authorized validation only.