Ecosyste.ms: Advisories

Security Advisories: MDE2OlNlY3VyaXR5QWR2aXNvcnlHSFNBLTk0aGgtcGpqZy1yd21y

Padding Oracle Attack due to Observable Timing Discrepancy in jose-browser-runtime

Impact

AES_CBC_HMAC_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.

Permalink: https://github.com/advisories/GHSA-94hh-pjjg-rwmr
JSON: https://advisories.ecosyste.ms/api/v1/advisories/MDE2OlNlY3VyaXR5QWR2aXNvcnlHSFNBLTk0aGgtcGpqZy1yd21y
Source: GitHub Advisory Database
Origin: Unspecified
Severity: Moderate
Classification: General
Published: about 3 years ago
Updated: about 1 year ago

CVSS Score: 5.9
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Identifiers: GHSA-94hh-pjjg-rwmr, CVE-2021-29444
References:

• https://github.com/panva/jose/security/advisories/GHSA-94hh-pjjg-rwmr
• https://www.npmjs.com/package/jose-browser-runtime
• https://nvd.nist.gov/vuln/detail/CVE-2021-29444
• https://github.com/advisories/GHSA-94hh-pjjg-rwmr

Repository: https://github.com/panva/jose
Blast Radius: 5.9

Affected Packages