Cyber Resilience

CVE-2024-20439

Exposed Creds in Cisco Smart License Utility 2.0.0 – 2.3.0

CISA KEVActive ExploitationEUVD ExploitedExposed Creds
Published
04 September 2024
Modified
28 October 2025
KEV Added
31 March 2025
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.92 99.8th percentile
Risk Priority 97 floored blend · peak EPSS

Summary

CVE-2024-20439 is a critical-severity Hidden Functionality (CWE-912) vulnerability in Cisco Smart License Utility. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Unsecured Credentials (T1552); ranked in the top 0.2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

The strongest mitigations our analysis identified map to CM-2 (Baseline Configuration) and CM-7 (Least Functionality) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2024-20439 is a vulnerability in Cisco Smart Licensing Utility (CSLU) stemming from an undocumented static administrative credential. The flaw, tracked under CWE-798 and CWE-912, permits unauthenticated remote access to the CSLU application API with full administrative privileges and carries a CVSS 3.1 score of 9.8.

An unauthenticated remote attacker can exploit the hardcoded credential to log directly into an affected CSLU instance. Successful exploitation grants administrative control over the licensing utility's API, enabling arbitrary actions within the application without any user interaction or prior authentication.

The Cisco Security Advisory at sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cslu-7gHMzWmw and the CISA Known Exploited Vulnerabilities catalog both address the issue, with CISA listing the CVE as actively exploited in the wild. The associated EPSS score stands at 0.8715, indicating substantial exploitation likelihood.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

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.…

more

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.

CWE(s)
KEV Date Added
31 March 2025

Related Threats

MITRE ATT&CK Enterprise Techniques

T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
T1552.001 Credentials In Files Credential Access
Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials.
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
T1078.001 Default Accounts Stealth
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
T1108 Redundant Access Stealth
**This technique has been deprecated.
T1505 Server Software Component Persistence
Adversaries may abuse legitimate extensible development features of servers to establish persistent access to systems.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-20440Same product: Cisco Smart License Utility
CVE-2026-20316Same vendor: Ciscoboth on KEV
CVE-2026-20128Same vendor: Ciscoboth on KEV
CVE-2026-20349Same vendor: Ciscoboth on KEV
CVE-2026-20133Same vendor: Ciscoboth on KEV
CVE-2016-6415Same vendor: Ciscoboth on KEV
CVE-2020-3259Same vendor: Ciscoboth on KEV
CVE-2022-20821Same vendor: Ciscoboth on KEV
CVE-2026-20127Same vendor: Ciscoboth on KEV
CVE-2026-20182Same vendor: Ciscoboth on KEV

Affected Assets

cisco
smart license utility
2.0.0 — 2.3.0

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Maintaining and reviewing a documented baseline configuration allows comparison that reveals any functionality absent from the approved specification.

Least-functionality configuration explicitly prohibits or restricts any capability not required by the approved baseline, blocking hidden additions.

Authenticator management requires secure distribution and handling of credentials, structurally discouraging hard-coded values.

Developer testing and evaluation activities are designed to discover undocumented or unspecified functionality after it has been introduced.

Cryptographic key management mandates proper establishment and handling instead of embedding keys in code.

Documented development processes and standards require all functionality to be specified and visible, structurally preventing undocumented hidden features.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 full match
prevents

Secure SDLC practices directly prevent introduction of undocumented hidden functionality during development.

ID.RA-09 mostly match
prevents

Pre-acquisition integrity/authenticity checks can detect undocumented hidden functions in supplied software/hardware.

PR.AA-01 partial match
prevents

PR.AA-01's credential/key-management processes can reduce the incentive to embed secrets but do not address or detect hard-coded values in source code, so the weakness remains fully possible.

PR.AA-02 none match
prevents

PR.AA-02 addresses human identity proofing and per-person credential issuance at enrollment; it has no bearing on whether developers embed static credentials in software.

PR.DS-01 none match
prevents

PR.DS-01 addresses encryption and integrity of stored data but never touches credential or key management practices, so it neither prevents hard-coded credentials nor removes any of their risk.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing in development and acceptance can discover undocumented functionality before release.

prevents

Change management processes can catch unauthorized additions but do not inherently prevent hidden functionality from being introduced.

prevents

Education on secure configuration practices discourages technical staff from embedding or relying on hard-coded credentials in systems and applications.

finds

Monitoring activities can detect anomalous behavior from hidden functions but do not eliminate the weakness.

mitigates

Secure key-generation, distribution and storage procedures reduce the likelihood that hard-coded or default cryptographic keys will be introduced or left unprotected.

prevents

Secure development life cycle mandates documented requirements and design reviews that would expose undocumented hidden functionality.

References