[ANNOUNCEMENT] openssl 1.0.2r-1

Corinna Vinschen corinna-cygwin@cygwin.com
Fri Mar 1 21:22:00 GMT 2019

The following packages have been uploaded to the Cygwin distribution:

* openssl-1.0.2r-1
* openssl-devel-1.0.2r-1
* openssl-perl-1.0.2r-1
* libopenssl100-1.0.2r-1

The OpenSSL toolkit provides support for secure communications between
machines. OpenSSL includes a certificate management tool and shared
libraries which provide various cryptographic algorithms and protocols.

 Changes between 1.0.2q and 1.0.2r [26 Feb 2019]

  *) 0-byte record padding oracle

     If an application encounters a fatal protocol error and then calls
     SSL_shutdown() twice (once to send a close_notify, and once to receive one)
     then OpenSSL can respond differently to the calling application if a 0 byte
     record is received with invalid padding compared to if a 0 byte record is
     received with an invalid MAC. If the application then behaves differently
     based on that in a way that is detectable to the remote peer, then this
     amounts to a padding oracle that could be used to decrypt data.

     In order for this to be exploitable "non-stitched" ciphersuites must be in
     use. Stitched ciphersuites are optimised implementations of certain
     commonly used ciphersuites. Also the application must call SSL_shutdown()
     twice even if a protocol error has occurred (applications should not do
     this but some do anyway).

     This issue was discovered by Juraj Somorovsky, Robert Merget and Nimrod
     Aviram, with additional investigation by Steven Collison and Andrew
     Hourselt. It was reported to OpenSSL on 10th December 2018.
     [Matt Caswell]

  *) Move strictness check from EVP_PKEY_asn1_new() to EVP_PKEY_asn1_add0().
     [Richard Levitte]

 Changes between 1.0.2p and 1.0.2q [20 Nov 2018]

  *) Microarchitecture timing vulnerability in ECC scalar multiplication

     OpenSSL ECC scalar multiplication, used in e.g. ECDSA and ECDH, has been
     shown to be vulnerable to a microarchitecture timing side channel attack.
     An attacker with sufficient access to mount local timing attacks during
     ECDSA signature generation could recover the private key.

     This issue was reported to OpenSSL on 26th October 2018 by Alejandro
     Cabrera Aldaya, Billy Brumley, Sohaib ul Hassan, Cesar Pereida Garcia and
     Nicola Tuveri.
     [Billy Brumley]

  *) Timing vulnerability in DSA signature generation

     The OpenSSL DSA signature algorithm has been shown to be vulnerable to a
     timing side channel attack. An attacker could use variations in the signing
     algorithm to recover the private key.

     This issue was reported to OpenSSL on 16th October 2018 by Samuel Weiser.
     [Paul Dale]

  *) Resolve a compatibility issue in EC_GROUP handling with the FIPS Object
     Module, accidentally introduced while backporting security fixes from the
     development branch and hindering the use of ECC in FIPS mode.
     [Nicola Tuveri]

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