Security Vulnerability: AWS-LC has PKCS7_verify Certificate Chain Validation Bypass

[tvpeter]

Summary

AWS-LC is an open-source, general-purpose cryptographic library.

Impact

Improper certificate validation in PKCS7_verify() in AWS-LC allows an unauthenticated user to bypass certificate chain verification when processing PKCS7 objects with multiple signers, except the final signer.

Customers of AWS services do not need to take action. aws-lc-sys contains code from AWS-LC. Applications using aws-lc-sys should upgrade to the most recent release of aws-lc-sys.

Impacted versions:

aws-lc-sys versions: >= 0.24.0, < 0.38.0

Patches

The patch is included in v0.38.0

Workarounds

There is no workaround. Applications using aws-lc-sys should upgrade to the most recent release of aws-lc-sys.

Resources

If there are any questions or comments about this advisory, contact [AWS/Amazon] Security via the vulnerability reporting page or directly via email to aws-security@amazon.com. Please do not create a public GitHub issue.

Acknowledgement

AWS-LC would like to thank Joshua Rogers (https://joshua.hu/) for collaborating on this issue through the coordinated vulnerability disclosure process.