Apple has released a security advisory and updated software to address the OpenSSL TLS and AES-NI denial of service vulnerability.
OpenSSL contains a vulnerability that could an unauthenticated, remote attacker to cause a denial of service (DoS) condition.
The vulnerability is due to improper handling of Cipher Block Chaining (CBC) cipher suites in the Transport Layer Security (TLS) 1.1 and TLS 1.2 versions used in the affected software. An unauthenticated, remote attacker could exploit the vulnerability by using an unspecified vector to cause a DoS condition on the targeted system.
Functional code that exploits this vulnerability is publicly available as part of the Metasploit framework.
OpenSSL has confirmed the vulnerability and released software updates.
OpenSSL version 1.0.1c is vulnerable.
The vulnerability is exploitable through the AES-NI platform for TLS 1.2 or TLS 1.1 implemented on OpenSSL version 1.0.1c. OpenSSL platforms that do not support AES-NI or versions of OpenSSL that do not implement TLS 1.2 or 1.1, such as OpenSSL 0.9.8 and 1.0.0, are not affected.
OpenSSL has released a security advisory at the following link: secadv_20130204
Apple has released a security advisory at the following link: HT5880
An unauthenticated, remote attacker could exploit the vulnerability to cause the affected software to stop responding. This could result in a DoS condition for the legitimate applications that use the affected software for secure transmission services.
The vulnerability is due to improper implementation of the Advanced Encryption Standard New Instructions (AES-NI) standard in the affected software.
An unauthenticated, remote attacker could exploit the vulnerability by an unspecified vector to cause a DoS condition on the targeted system.
Administrators are advised to apply the appropriate updates.
Administrators may consider using an alternate product.
Administrators are advised to monitor critical systems.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
OpenSSL has released updated versions at the following link: OpenSSL 1.0.1d
Apple has released updated software at the following links:
The security vulnerability applies to the following combinations of products.
Mac OS X
10.6.8 Base | 10.7.5 Base | 10.8 Base | 10.8.1 Base | 10.8.2 Base | 10.8.3 Base | 10.8.4 Base
Mac OS X Server
10.6.8 Base | 10.7.5 Base
6.3 Base | 6.4 Base | 7.0 Base | 7.1 Base | 7.2 Base | 7.3 Base | 7.4 Base | 8.0 Base | 8.1 Base | 8.2 Base | 8.3 Base | 9.0 Base | 9.1 Base
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