We have discovered a security vulnerability in RT 4.2.x, detailed below.We are releasing RT version 4.2.8 to resolve this vulnerability, as well as patches which apply atop all released versions of 4.2.
RT 4.2.0 and above may be vulnerable to arbitrary execution of code by way of CVE-2014-7169, CVE-2014-7186, CVE-2014-7187, CVE-2014-6277, or CVE-2014-6271 -- collectively known as "Shellshock." This vulnerability requires a privileged user with access to an RT instance running with SMIME integration enabled; it applies to both mod_perl and fastcgi deployments. If you have already taken upgrades to bash to resolve "Shellshock," you are protected from this vulnerability in RT, and there is no need to apply this patch. This vulnerability has been assigned CVE-2014-7227.
As there is no SMIME integration available for RT 4.0, it is not vulnerable to this attack. The RT-Crypt-SMIME extension for RT 3.6.0, while also vulnerable, is no longer supported.
Patches for all releases of 4.2.x are available (signature). Versions of RT older than 4.0.0 are unsupported and do not receive security patches; please contact sales@bestpractical.com if you need assistance with an older RT version.
The README in the tarball contains instructions for applying the patches. If you need help resolving this issue locally, we will provide discounted pricing for single-incident support; please contact us at sales@bestpractical.com for more information.