CVE-2022-26320

The Rambus SafeZone Basic Crypto Module before 10.4.0, as used in certain Fujifilm (formerly Fuji Xerox) devices before 2022-03-01, Canon imagePROGRAF and imageRUNNER devices through 2022-03-14, and potentially many other devices, generates RSA keys that can be broken with Fermats factorization method. This allows efficient calculation of private RSA keys from the public key of a TLS certificate.

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://fermatattack.secvuln.info
• https://global.canon/en/support/security/index.html
• https://safezoneswupdate.com
• https://www.fujifilm.com/fbglobal/eng/company/news/notice/2022/0302_rsakey_announce.html