USN-1357-1: OpenSSL vulnerabilities

9 February 2012

openssl vulnerabilities

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

  • Ubuntu 11.10
  • Ubuntu 11.04
  • Ubuntu 10.10
  • Ubuntu 10.04 LTS
  • Ubuntu 8.04 LTS

Summary

Multiple vulnerabilities exist in OpenSSL that could expose sensitive information or cause applications to crash.

Software Description

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

Details

It was discovered that the elliptic curve cryptography (ECC) subsystem in OpenSSL, when using the Elliptic Curve Digital Signature Algorithm (ECDSA) for the ECDHE_ECDSA cipher suite, did not properly implement curves over binary fields. This could allow an attacker to determine private keys via a timing attack. This issue only affected Ubuntu 8.04 LTS, Ubuntu 10.04 LTS, Ubuntu 10.10 and Ubuntu 11.04. (CVE-2011-1945)

Adam Langley discovered that the ephemeral Elliptic Curve Diffie-Hellman (ECDH) functionality in OpenSSL did not ensure thread safety while processing handshake messages from clients. This could allow a remote attacker to cause a denial of service via out-of-order messages that violate the TLS protocol. This issue only affected Ubuntu 8.04 LTS, Ubuntu 10.04 LTS, Ubuntu 10.10 and Ubuntu 11.04. (CVE-2011-3210)

Nadhem Alfardan and Kenny Paterson discovered that the Datagram Transport Layer Security (DTLS) implementation in OpenSSL performed a MAC check only if certain padding is valid. This could allow a remote attacker to recover plaintext. (CVE-2011-4108)

Antonio Martin discovered that a flaw existed in the fix to address CVE-2011-4108, the DTLS MAC check failure. This could allow a remote attacker to cause a denial of service. (CVE-2012-0050)

Ben Laurie discovered a double free vulnerability in OpenSSL that could be triggered when the X509_V_FLAG_POLICY_CHECK flag is enabled. This could allow a remote attacker to cause a denial of service. This issue only affected Ubuntu 8.04 LTS, Ubuntu 10.04 LTS, Ubuntu 10.10 and Ubuntu 11.04. (CVE-2011-4109)

It was discovered that OpenSSL, in certain circumstances involving ECDH or ECDHE cipher suites, used an incorrect modular reduction algorithm in its implementation of the P-256 and P-384 NIST elliptic curves. This could allow a remote attacker to obtain the private key of a TLS server via multiple handshake attempts. This issue only affected Ubuntu 8.04 LTS. (CVE-2011-4354)

Adam Langley discovered that the SSL 3.0 implementation in OpenSSL did not properly initialize data structures for block cipher padding. This could allow a remote attacker to obtain sensitive information. (CVE-2011-4576)

Andrew Chi discovered that OpenSSL, when RFC 3779 support is enabled, could trigger an assert when handling an X.509 certificate containing certificate-extension data associated with IP address blocks or Autonomous System (AS) identifiers. This could allow a remote attacker to cause a denial of service. (CVE-2011-4577)

Adam Langley discovered that the Server Gated Cryptography (SGC) implementation in OpenSSL did not properly handle handshake restarts. This could allow a remote attacker to cause a denial of service. (CVE-2011-4619)

Andrey Kulikov discovered that the GOST block cipher engine in OpenSSL did not properly handle invalid parameters. This could allow a remote attacker to cause a denial of service via crafted data from a TLS client. This issue only affected Ubuntu 11.10. (CVE-2012-0027)

Update instructions

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

Ubuntu 11.10
libssl1.0.0 - 1.0.0e-2ubuntu4.2
openssl - 1.0.0e-2ubuntu4.2
Ubuntu 11.04
libssl0.9.8 - 0.9.8o-5ubuntu1.2
openssl - 0.9.8o-5ubuntu1.2
Ubuntu 10.10
libssl0.9.8 - 0.9.8o-1ubuntu4.6
openssl - 0.9.8o-1ubuntu4.6
Ubuntu 10.04 LTS
libssl0.9.8 - 0.9.8k-7ubuntu8.8
openssl - 0.9.8k-7ubuntu8.8
Ubuntu 8.04 LTS
libssl0.9.8 - 0.9.8g-4ubuntu3.15
openssl - 0.9.8g-4ubuntu3.15

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