USN-2959-1: OpenSSL vulnerabilities

3 May 2016

Several security issues were fixed in OpenSSL.

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Releases

Packages

  • openssl - Secure Socket Layer (SSL) cryptographic library and tools

Details

Huzaifa Sidhpurwala, Hanno Böck, and David Benjamin discovered that OpenSSL
incorrectly handled memory when decoding ASN.1 structures. A remote
attacker could use this issue to cause OpenSSL to crash, resulting in a
denial of service, or possibly execute arbitrary code. (CVE-2016-2108)

Juraj Somorovsky discovered that OpenSSL incorrectly performed padding when
the connection uses the AES CBC cipher and the server supports AES-NI. A
remote attacker could possibly use this issue to perform a padding oracle
attack and decrypt traffic. (CVE-2016-2107)

Guido Vranken discovered that OpenSSL incorrectly handled large amounts of
input data to the EVP_EncodeUpdate() function. A remote attacker could use
this issue to cause OpenSSL to crash, resulting in a denial of service, or
possibly execute arbitrary code. (CVE-2016-2105)

Guido Vranken discovered that OpenSSL incorrectly handled large amounts of
input data to the EVP_EncryptUpdate() function. A remote attacker could use
this issue to cause OpenSSL to crash, resulting in a denial of service, or
possibly execute arbitrary code. (CVE-2016-2106)

Brian Carpenter discovered that OpenSSL incorrectly handled memory when
ASN.1 data is read from a BIO. A remote attacker could possibly use this
issue to cause memory consumption, resulting in a denial of service.
(CVE-2016-2109)

As a security improvement, this update also modifies OpenSSL behaviour to
reject DH key sizes below 1024 bits, preventing a possible downgrade
attack.

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 16.04
Ubuntu 15.10
Ubuntu 14.04
Ubuntu 12.04

After a standard system update you need to reboot your computer to make
all the necessary changes.