USN-2959-1: OpenSSL vulnerabilities

3 May 2016

openssl vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 16.04 LTS
  • Ubuntu 15.10
  • Ubuntu 14.04 LTS
  • Ubuntu 12.04 LTS

Summary

Several security issues were fixed in OpenSSL.

Software Description

  • 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.

Update instructions

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

Ubuntu 16.04 LTS
libssl1.0.0 - 1.0.2g-1ubuntu4.1
Ubuntu 15.10
libssl1.0.0 - 1.0.2d-0ubuntu1.5
Ubuntu 14.04 LTS
libssl1.0.0 - 1.0.1f-1ubuntu2.19
Ubuntu 12.04 LTS
libssl1.0.0 - 1.0.1-4ubuntu5.36

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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

References