Headline
CVE-2021-26109: Fortiguard
An integer overflow or wraparound vulnerability in the memory allocator of SSLVPN in FortiOS before 7.0.1 may allow an unauthenticated attacker to corrupt control data on the heap via specifically crafted requests to SSLVPN, resulting in potentially arbitrary code execution.
PSIRT Advisories
FortiOS - Integer overflow in SSLVPN allocator
Summary
An integer overflow or wraparound vulnerability [CWE-190] in FortiOS SSLVPN memory allocator may allow an unauthenticated attacker to corrupt control data on the heap via specifically crafted requests to SSLVPN, resulting in potentially arbitrary code execution.
Affected Products
FortiOS version 7.0.0 and below.
FortiOS version 6.4.5 and below.
FortiOS version 6.2.9 and below.
FortiOS version 6.0.12 and below.
Solutions
Upgrade to FortiOS 7.0.1.
Upgrade to FortiOS 6.4.6.
Upgrade to FortiOS 6.2.10.
Upgrade to FortiOS 6.0.13.
For new high-end F-Series Models (FG-1800F, FG-3800F, FG-4200F, FG-4400F) please upgrade to 6.2.9
Acknowledgement
Internally discovered and reported by Giuseppe Cocomazzi of Fortinet Product Security team.