Id:
CVE-2021-29443
Comment
:
jose is an npm library providing a number of cryptographic operations. In vulnerable versions 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. 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). All major release versions have had a patch released which ensures the HMAC tag is verified before performing CBC decryption. The fixed versions are `^1.28.1 || ^2.0.5 || >=3.11.4`. Users should upgrade their v1.x dependency to ^1.28.1, their v2.x dependency to ^2.0.5, and their v3.x dependency to ^3.11.4. Thanks to Jason from Microsoft Vulnerability Research (MSVR) for bringing this up and Eva Sarafianou (@esarafianou) for helping to score this advisory.
CVSSv2 Score:
4.3
Access vector:
|
NETWORK
|
Access complexity:
|
MEDIUM
|
Authentication:
|
NONE
|
Confidentiality impact:
|
PARTIAL
|
Integrity impact:
|
NONE
|
Availability impact:
|
NONE
|
CVSSv2 Vector:
AV:N/AC:M/Au:N/C:P/I:N/A:N
CVSSv3 Score:
5.9
Attack vector:
|
NETWORK
|
Attack complexity:
|
HIGH
|
Privileges required:
|
NONE
|
User interaction:
|
NONE
|
Scope:
|
UNCHANGED
|
Confidentiality impact:
|
HIGH
|
Integrity impact:
|
NONE
|
Availability impact:
|
NONE
|
CVSSv3 Vector:
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
References: