CVE-2016-7055 log

Source
Severity Low
Remote Yes
Type Incorrect calculation
Description
There is a carry propagating bug in the Broadwell-specific Montgomery multiplication procedure that handles input lengths divisible by, but longer than 256 bits. Analysis suggests that attacks against RSA, DSA and DH private keys are impossible. This is because the subroutine in question is not used in operations with the private key itself and an input of the attacker's direct choice. Otherwise the bug can manifest itself as transient authentication and key negotiation failures or reproducible erroneous outcome of public-key operations with specially crafted input. Among EC algorithms only Brainpool P-512 curves are affected and one presumably can attack ECDH key negotiation. Impact was not analyzed in detail, because pre-requisites for attack are considered unlikely. Namely multiple clients have to choose the curve in question and the server has to share the private key among them, neither of which is default behavior. Even then only clients that chose the curve will be affected.
Group Package Affected Fixed Severity Status Ticket
AVG-155 lib32-openssl 1:1.0.2.j-1 1:1.0.2.k-1 Medium Fixed
AVG-154 openssl 1.0.2.j-1 1.0.2.k-1 Medium Fixed
AVG-68 lib32-openssl 1:1.0.2.j-1 1:1.0.2.k-1 Low Fixed
AVG-67 openssl 1.0.2.j-1 1.0.2.k-1 Low Fixed
Date Advisory Group Package Severity Description
28 Jan 2017 ASA-201701-37 AVG-154 openssl Medium multiple issues
27 Jan 2017 ASA-201701-36 AVG-155 lib32-openssl Medium multiple issues
References
https://www.openssl.org/news/secadv/20161110.txt
https://github.com/openssl/openssl/commit/57c4b9f6a2f800b41ce2836986fe33640f6c3f8a