Dr S N Henson of the OpenSSL core team and Open Network Security recently developed an ASN1 test suite for NISCC (www.niscc.gov.uk). When the test suite was run against OpenSSL a denial of service vulnerability was discovered. Certain types of public key can take disproportionate amounts of time to process. This could be used by an attacker in a denial of service attack. CVE-2006-2940 Any code which uses OpenSSL to parse ASN1 data from untrusted sources is affected. This includes SSL servers which enable client authentication and S/MIME applications. This issue was co-ordinated through NISCC although currently no patch exists. The final patch will reject keys which exceed certain limits. These limits are similar to those already enforced by other crypto libraries such as NSS. Embargo until 20060928 Also affects (all RHEL)
Created attachment 137035 [details] proposed patch CVE-2006-2940
Created attachment 137036 [details] replacement patch CVE-2006-2940
removing embargo, public at http://www.openssl.org/news/secadv_20060928.txt
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on the solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2006-0695.html