A download of code without Integrity check vulnerability [CWE-494] in FortiClientMac version 7.0.0 through 7.0.7, 6.4 all versions, 6.2 all versions, 6.0 all versions, 5.6 all versions, 5.4 all versions, 5.2 all versions, 5.0 all versions and 4.0 all versions may allow a local attacker to escalate their privileges via modifying the installer upon upgrade.

An improper symlink following in FortiClient for Mac 6.4.3 and below may allow an non-privileged user to execute arbitrary privileged shell commands during installation phase.

An Improper Neutralization of Special Elements used in a Command vulnerability in one of FortiClient for Mac OS root processes, may allow a local user of the system on which FortiClient is running to execute unauthorized code as root by bypassing a security check.

Use of a hardcoded cryptographic key in the FortiGuard services communication protocol may allow a Man in the middle with knowledge of the key to eavesdrop on and modify information (URL/SPAM services in FortiOS 5.6, and URL/SPAM/AV services in FortiOS 6.0.; URL rating in FortiClient) sent and received from Fortiguard severs by decrypting these messages. Affected products include FortiClient for Windows 6.0.6 and below, FortiOS 6.0.7 and below, FortiClient for Mac OS 6.2.1 and below.

Users' VPN authentication credentials are unsafely encrypted in Fortinet FortiClient for Windows 5.6.0 and below versions, FortiClient for Mac OSX 5.6.0 and below versions and FortiClient SSLVPN Client for Linux 4.4.2335 and below versions, due to the use of a static encryption key and weak encryption algorithms.

An Information Disclosure vulnerability in Fortinet FortiClient for Windows 5.6.0 and below versions, FortiClient for Mac OSX 5.6.0 and below versions and FortiClient SSLVPN Client for Linux 4.4.2334 and below versions allows regular users to see each other's VPN authentication credentials due to improperly secured storage locations.

The (1) mdare64_48.sys, (2) mdare32_48.sys, (3) mdare32_52.sys, (4) mdare64_52.sys, and (5) Fortishield.sys drivers in Fortinet FortiClient before 5.2.4 do not properly restrict access to the API for management of processes and the Windows registry, which allows local users to obtain a privileged handle to a PID and possibly have unspecified other impact, as demonstrated by a 0x2220c8 ioctl call.

The Fortishield.sys driver in Fortinet FortiClient before 5.2.4 allows local users to execute arbitrary code with kernel privileges by setting the callback function in a (1) 0x220024 or (2) 0x220028 ioctl call.

The (1) mdare64_48.sys, (2) mdare32_48.sys, (3) mdare32_52.sys, and (4) mdare64_52.sys drivers in Fortinet FortiClient before 5.2.4 allow local users to write to arbitrary memory locations via a 0x226108 ioctl call.

The (1) mdare64_48.sys, (2) mdare32_48.sys, (3) mdare32_52.sys, and (4) mdare64_52.sys drivers in Fortinet FortiClient before 5.2.4 allow local users to read arbitrary kernel memory via a 0x22608C ioctl call.

FortiClient before 4.3.5.472 on Windows, before 4.0.3.134 on Mac OS X, and before 4.0 on Android; FortiClient Lite before 4.3.4.461 on Windows; FortiClient Lite 2.0 through 2.0.0223 on Android; and FortiClient SSL VPN before 4.0.2258 on Linux proceed with an SSL session after determining that the server's X.509 certificate is invalid, which allows man-in-the-middle attackers to obtain sensitive information by leveraging a password transmission that occurs before the user warning about the certificate problem.