A flaw  was found in OpenSSL 0.9.8h through 0.9.8q and 1.0.0 through 1.0.0c where an incorrectly formatted ClientHello handshake message could cause OpenSSL to parse past the end of the message. An attacker could use this flaw to trigger an invalid memory access, causing a crash of an application linked to OpenSSL. As well, certain applications may expose the contents of parsed OCSP extensions, specifically the OCSP nonce extension.
Applications are only affected if they act as a server and call SSL_CTX_set_tlsext_status_cb on the server's SSL_CTX. One such application is Apache httpd >= 2.3.3.
This issue was addressed in OpenSSL versions 0.9.8r and 1.0.0d. A patch is included in the upstream advisory .
Created mingw32-openssl tracking bugs for this issue
Affects: fedora-all [bug 676070]
Created openssl tracking bugs for this issue
Affects: fedora-all [bug 676069]
The flaw exists in the code for parsing TLS status_request extension. Support for that extension was introduced in version 0.9.8h via this upstream commit:
Therefore, this issue does not affect openssl packages in Red Hat Enterprise Linux 3, 4 and 5. Only openssl packages in Red Hat Enterprise Linux 6 are affected.
Upstream advisory also mentions that this issue only affects server applications that call SSL_CTX_set_tlsext_status_cb to set status_request extension callback function. The only application shipped with Red Hat Enterprise Linux 6 using this function is openssl's testing s_server application.
As noted above, this OpenSSL feature is not used by any application shipped with Red Hat Enterprise Linux 6. Given the limited impact and the lack of affected applications, we plan to address this as part of openssl update in Red Hat Enterprise Linux 6.1.
This issue did not affect the versions of openssl as shipped with Red Hat Enterprise Linux 3, 4, and 5. It was addressed in Red Hat Enterprise Linux 6 via RHSA-2011:0677.
This issue has been addressed in following products:
Red Hat Enterprise Linux 6
Via RHSA-2011:0677 https://rhn.redhat.com/errata/RHSA-2011-0677.html