OpenSSL v1.0.2.j Release Notes
Release Date: 2017-01-26 // over 7 years ago-
- Truncated packet could crash via OOB read
If one side of an SSL/TLS path is running on a 32-bit host and a specific cipher is being used, then a truncated packet can cause that host to perform an out-of-bounds read, usually resulting in a crash.
This issue was reported to OpenSSL by Robert Święcki of Google. [CVE-2017-3731][]
Andy Polyakov
- BN_mod_exp may produce incorrect results on x86_64
There is a carry propagating bug in the x86_64 Montgomery squaring procedure. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be very significant and likely only accessible to a limited number of attackers. An attacker would additionally need online access to an unpatched system using the target private key in a scenario with persistent DH parameters and a private key that is shared between multiple clients. For example this can occur by default in OpenSSL DHE based SSL/TLS ciphersuites. Note: This issue is very similar to CVE-2015-3193 but must be treated as a separate problem.
This issue was reported to OpenSSL by the OSS-Fuzz project. [CVE-2017-3732][]
Andy Polyakov
- Montgomery multiplication may produce incorrect results
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 behaviour. Even then only clients that chose the curve will be affected.
This issue was publicly reported as transient failures and was not initially recognized as a security issue. Thanks to Richard Morgan for providing reproducible case. [CVE-2016-7055][]
Andy Polyakov
- OpenSSL now fails if it receives an unrecognised record type in TLS1.0 or TLS1.1. Previously this only happened in SSLv3 and TLS1.2. This is to prevent issues where no progress is being made and the peer continually sends unrecognised record types, using up resources processing them.
Matt Caswell