CVE-2023-20016

A vulnerability in the backup configuration feature of Cisco UCS Manager Software and in the configuration export feature of Cisco FXOS Software could allow an unauthenticated attacker with access to a backup file to decrypt sensitive information stored in the full state and configuration backup files. This vulnerability is due to a weakness in the encryption method used for the backup function. An attacker could exploit this vulnerability by leveraging a static key used for the backup configuration feature. A successful exploit could allow the attacker to decrypt sensitive information that is stored in full state and configuration backup files, such as local user credentials, authentication server passwords, Simple Network Management Protocol (SNMP) community names, and other credentials.

Weakness

The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.

Affected Software

Potential Mitigations

• Use a well-vetted algorithm that is currently considered to be strong by experts in the field, and select well-tested implementations with adequate length seeds.
• In general, if a pseudo-random number generator is not advertised as being cryptographically secure, then it is probably a statistical PRNG and should not be used in security-sensitive contexts.
• Pseudo-random number generators can produce predictable numbers if the generator is known and the seed can be guessed. A 256-bit seed is a good starting point for producing a “random enough” number.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/112.html
• https://cwe.mitre.org/data/definitions/485.html
• https://cwe.mitre.org/data/definitions/59.html

References

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ucsm-bkpsky-H8FCQgsA