GHSA-4v4g-726h-xvfv

Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/04/GHSA-4v4g-726h-xvfv/GHSA-4v4g-726h-xvfv.json

Aliases

• CVE-2021-29445

Published

2021-04-19T14:59:06Z

Modified

2023-03-17T17:49:46Z

Details

Impact

AESCBCHMAC_SHA2 Algorithm (A128CBC-HS256, A192CBC-HS384, A256CBC-HS512) decryption would always execute both HMAC tag verification and CBC decryption, if either failed JWEDecryptionFailed would be thrown. But a possibly observable difference in timing when padding error would occur while decrypting the ciphertext makes a padding oracle and an adversary might be able to make use of that oracle to decrypt data without knowing the decryption key by issuing on average 128*b calls to the padding oracle (where b is the number of bytes in the ciphertext block).

Patches

A patch was released which ensures the HMAC tag is verified before performing CBC decryption. The fixed versions are >=3.11.4.

Users should upgrade to ^3.11.4.

Credits

Thanks to Morgan Brown of Microsoft for bringing this up and Eva Sarafianou (@esarafianou) for helping to score this advisory.

References

• https://github.com/panva/jose/security/advisories/GHSA-4v4g-726h-xvfv
• https://nvd.nist.gov/vuln/detail/CVE-2021-29445
• https://github.com/panva/jose
• https://www.npmjs.com/package/jose-node-esm-runtime