CVE-2017-12972 Information

Description

In Nimbus JOSE+JWT before 4.39 there is no integer-overflow check when converting length values from bytes to bits which allows attackers to conduct HMAC bypass attacks by shifting Additional Authenticated Data (AAD) and ciphertext so that different plaintext is obtained for the same HMAC.

CVSS Vector

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Reference

https://bitbucket.org/connect2id/nimbus-jose-jwt/commits/0d2bd649ea386539220d4facfe1f65eb1dadb86c https://bitbucket.org/connect2id/nimbus-jose-jwt/issues/224/byte-to-bit-overflow-in-cbc https://bitbucket.org/connect2id/nimbus-jose-jwt/src/master/CHANGELOG.txt https://lists.apache.org/thread.html/9317fd092b257a0815434b116a8af8daea6e920b6673f4fd5583d5fe@3Ccommits.druid.apache.org3E

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

HIGH

Base Score

NONE

Base Severity

7.5