WHMCS Security Advisory TSR-2014-0002
WHMCS has released new updates for all supported versions of WHMCS. The updates were release to address security concerns within the WHMCS product.
The following updates were released to address the security concerns:
WHMCS v5.3.6
WHMCS v5.2.17
If you are using previous version, it is recommended that you upgrade to one of the above version. As always, WHMCS is released a patch as well as full release. If you are using WHMCS v5.3.5 or WHMCS v5.2.16, you can use the patch to apply this security update (WHMCS Security Advisory TSR-2014-0002).
If you have any questions or concerns about upgrading WHMCS, you can refer our article on upgrade WHMCS.