A vulnerability in OpenSSL could allow an unauthenticated, remote attacker to access sensitive information.
The vulnerability is due to a cipher block collision that may occur during an encrypted session where OpenSSL uses a 64-bit block cipher, such as 3DES Cipher Block Chaining (CBC) mode. An attacker who is able to capture nearly a terabyte of network traffic could exploit this vulnerability to monitor a cipher block collision, which could be leveraged to decrypt data in transit and gain access to sensitive information. A successful exploit could be leveraged to conduct further attacks.
Proof-of-concept code that exploits this vulnerability is available.
OpenSSL has confirmed the vulnerability and released software updates.
The vulnerability is due to a cipher block collision that may occur
during a long encrypted session where OpenSSL uses a 64-bit block cipher,
such as 3DES CBC mode.
To exploit this vulnerability, an attacker must be able to capture a large amount of network traffic. The attacker may require access to trusted, internal networks that are located behind a firewall or may utilize sniffing tools, which could be detected on an internal network. Administrators are advised to actively monitor their networks for the presence of sniffing tools.
The attack method that exploits this vulnerability is known as a SWEET32 attack.
This vulnerability only affects 64-bit block ciphers such as 3DES CBC mode or Blowfish.
Administrators are advised to apply the appropriate updates.
Administrators are advised to allow only trusted users to have network access.
Administrators can help protect affected systems from external attacks by using a solid firewall strategy.
Administrators are advised to monitor affected systems.
OpenSSL has released a changelog at the following link: CVE-2016-2183
Red Hat has released updated software for registered subscribers at the following link: Red Hat Network. Red Hat packages can be updated on Red Hat Enterprise Linux versions 5 and later by using the yum tool.
Text-Only Advisories x86_64 (Base) | 2 for RHEL 7 x86_64 (Base) | 2 for RHEL 6 x86_64 (Base) | 2 for RHEL 6 i386 (Base)
JBoss Core Services
1 for RHEL 6 (x86_64, ppc64, i386) | 1 for RHEL 7 (x86_64, ppc64) | Text-Only Advisories (x86_64)
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