The ESET Personal Firewall NDIS filter (EpFwNdis.sys) driver in the Firewall Module Build 1183 (20140214) and earlier in ESET Smart Security and ESET Endpoint Security products 5.0 through 7.0 allows local users to gain privileges via a crafted argument to a 0x830020CC IOCTL call.

Race condition in ESET Smart Security 4.2.35.3 on Windows XP allows local users to bypass kernel-mode hook handlers, and execute dangerous code that would otherwise be blocked by a handler but not blocked by signature-based malware detection, via certain user-space memory changes during hook-handler execution, aka an argument-switch attack or a KHOBE attack. NOTE: this issue is disputed by some third parties because it is a flaw in a protection mechanism for situations where a crafted program has already begun to execute

easdrv.sys in ESET Smart Security 3.0.667.0 allows local users to cause a denial of service (crash) via a crafted IOCTL 0x222003 request to the \\.\easdrv device interface.

The Personal Firewall driver (aka epfw.sys) 3.0.672.0 and earlier in ESET Smart Security 3.0.672 and earlier allows local users to gain privileges via a crafted IRP in a certain METHOD_NEITHER IOCTL request to \Device\Epfw that overwrites portions of memory.

ESET Smart Security, when Internet Explorer 6 or 7 is used, allows remote attackers to bypass detection of malware in an HTML document by placing an MZ header (aka "EXE info") at the beginning, and modifying the filename to have (1) no extension, (2) a .txt extension, or (3) a .jpg extension, as demonstrated by a document containing a CVE-2006-5745 exploit.