OpenSSL CRL bypass and ECDH Denial of Service Vulnerability

Release date: 2011-09-06
Updated on: 2011-09-06

Affected Systems:
OpenSSL Project OpenSSL 1.x
Description:
--------------------------------------------------------------------------------
Cve id: CVE-2011-3207, CVE-2011-3210

OpenSSL is an open-source SSL implementation that implements high-strength encryption for network communication. It is widely used in various network applications.

OpenSSL has the CRL bypass and ECDH denial of service vulnerability in internal certificate verification and the implementation of temporary ECDH cipher groups. Malicious users can exploit this vulnerability to bypass certain security restrictions and cause DOS.

1) errors in internal certificate verification can cause OpenSSL to accept the "nextUpdate" Field of CRL to be set to the past date.

2) An error in the temporary ECDH password group can lead to an invalid handshake message in the sequence, causing the affected server to crash.

<* Source: Kaspar Brand

Link: http://www.openssl.org/news/secadv_20110906.txt
*>

Suggestion:
--------------------------------------------------------------------------------
Vendor patch:

OpenSSL Project
---------------
The vendor has released a patch to fix this security problem. Please download it from the vendor's homepage:

Http://www.openssl.org/