CVE-2021-29499

SIF is an open source implementation of the Singularity Container Image Format. The siftool new command and func siftool.New() produce predictable UUID identifiers due to insecure randomness in the version of the github.com/satori/go.uuid module used as a dependency. A patch is available in version >= v1.2.3 of the module. Users are encouraged to upgrade. As a workaround, users passing CreateInfo struct should ensure the ID field is generated using a version of github.com/satori/go.uuid that is not vulnerable to this issue.

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://github.com/sylabs/sif/security/advisories/GHSA-4gh8-x3vv-phhg