CyberSecBulletin
CVE-2024-20439Exploited in the wildNVD status: Analyzed

Cisco Smart Licensing Utility Static Credential

CVE-2024-20439 is a critical-severity use of hard-coded credentials vulnerability in Cisco Smart License Utility from Cisco, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Cisco Smart License Utility versions: 2.1.0; 2.0.0; 2.2.0. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on March 31, 2025, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update Smart License Utility to 2.3.0 or a later version.
  2. CISA's 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.
  3. Read the advisory on sec.cloudapps.cisco.com for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
CiscoCisco Smart License Utility2.1.0; 2.0.0; 2.2.0Not stated
CiscoSmart License Utility2.0.0 up to, but not including, 2.3.02.3.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.8CriticalCNA (cisco.com)
CVSS 3.19.8CriticalNVD

Official 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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use of Hard-coded Credentials

The product contains hard-coded credentials, such as a password or cryptographic key.

How developers prevent this class of flaw

  • For outbound authentication: store passwords, keys, and other credentials outside of the code in a strongly-protected, encrypted configuration file or database that is protected from access by all outsiders, including other local users on the same system. Properly protect the key (CWE-320). If you cannot use encryption to protect the file, then make sure that the permissions are as restrictive as possible. In Windows environments, the Encrypted File System (EFS) may provide some protection.
  • For inbound authentication: Rather than hard-code a default username and password, key, or other authentication credentials for first time logins, utilize a first login mode that requires the user to enter a unique strong password or key.
  • If the product must contain hard-coded credentials or they cannot be removed, perform access control checks and limit which entities can access the feature that requires the hard-coded credentials. For example, a feature might only be enabled through the system console instead of through a network connection.

More Use of Hard-coded Credentials vulnerabilities (CWE-798)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: total).
  3. Added to CISA's Known Exploited Vulnerabilities catalogue.
  4. Deadline for US federal agencies to remediate, set by CISA.
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Cisco Smart License Utility

All Cisco Smart License Utility vulnerabilities

Recent Use of Hard-coded Credentials vulnerabilities

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