Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d4a44ac6b077019…

MALICIOUS

PDF

19.6 KB Created: 2013-05-14 18:56:07 +04:00 Authoring application: Adobe Designer 7.0 First seen: 2015-09-30
MD5: 9b48f04c1549f06e821312c0179f7d40 SHA-1: e2339671b9b63f8d7a8289f6e9b5689acf67f6ed SHA-256: 5d4a44ac6b0770197c4f4ab9e524c1093583b863194647ba152a5214c7f0459e
234 Risk Score

Malware Insights

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

The PDF file utilizes XFA forms and embedded JavaScript, triggering critical heuristics for XFA JavaScript heap spray exploits. The embedded JavaScript attempts to download a payload from 'http://cgi.adobe.com/special/acrobat/update', indicating an attempt to execute arbitrary code. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 10

  • XFA form contains risky executable script high CVE related PDF_XFA_SCRIPT
    PDF embeds an XFA form whose script block contains exploit, submission/launch, or shell-execution primitives. Ordinary LiveCycle print/update scripts are left as generic XFA/JS signals unless stronger behavior is present.
  • XFA JavaScript heap-spray exploit code critical PDF_XFA_HEAP_SPRAY
    PDF contains XFA script content with heap-spray or shellcode-like JavaScript markers such as large encoded word sequences, util.pack, large arrays, or spray variable names. This is a weaponised Adobe Reader exploit pattern, not a normal interactive form.
  • 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 JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • 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.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • AcroForm button with action trigger low PDF_ACROFORM_BUTTON
    PDF contains a /Btn form field together with a SubmitForm/URI/Launch/JS trigger — this is the building block of fake 'Download' or 'Open' button overlays used in PDF phishing lures
  • Embedded script payload in PDF stream info PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain an HTML/XFA <script> tag without accompanying Windows shell-execution primitives — common in accessible XFA forms but worth surfacing for analyst review.
  • 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/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/pdf/1.3/In PDF document text
    • http://cgi.adobe.com/special/acrobat/updateReferenced by PDF JavaScript
    • http://www.xfa.org/schema/xfa-template/2.1/Referenced by PDF JavaScript
    • http://www.xfa.org/schema/xfa-template/2.2/Referenced by PDF JavaScript
    • http://www.xfa.org/schema/xfa-template/2.0/Referenced by PDF JavaScript
    • http://ns.adobe.com/xdp/In PDF document text
    • http://www.xfa.org/schema/xci/1.0/In PDF document text
    • http://www.xfa.org/schema/xfa-data/1.0/In PDF document text
    • http://www.xfa.org/schema/xfa-locale-set/2.1/In PDF document text
    • http://ns.adobe.com/xtd/In PDF document text

Extracted artifacts 9

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0027.bin pdf-embedded-file PDF EmbeddedFile object 27 at offset 0x222C 85 bytes
SHA-256: c06dcd026a7ea0536b63e07ce688691b585339a3ab7ff59065e546b56308c7bb
embedded_file_obj0028.bin pdf-embedded-file PDF EmbeddedFile object 28 at offset 0x22DE 1520 bytes
SHA-256: 7819f06630520bfd73f8079eece39a31ed650dc5a0392d84cc1a95b60eb179d9
embedded_file_obj0029.bin pdf-embedded-file PDF EmbeddedFile object 29 at offset 0x25AB 9116 bytes
SHA-256: bb8d185a5695297ff23dd6d29be744dfa151f4a6cda7bf353353f10a51d7b872
embedded_file_obj0030.bin pdf-embedded-file PDF EmbeddedFile object 30 at offset 0x377E 503 bytes
SHA-256: 263709bb5b977e1bad72663748529c02d9396c006f0460355723babeb7391f2b
embedded_file_obj0031.bin pdf-embedded-file PDF EmbeddedFile object 31 at offset 0x3878 4643 bytes
SHA-256: e705f8fbc86048d63338b8eee28deb3965d674af1b338994f05e4470e86f53c9
embedded_file_obj0032.bin pdf-embedded-file PDF EmbeddedFile object 32 at offset 0x3CD1 212 bytes
SHA-256: 57045217c453d4674a08ad8778674bf199a7989a9505424a1815c016e6bb412f
javascript_obj0019_000.js pdf-javascript-stream PDF /JS object 19 at offset 0x1AB5 870 bytes
SHA-256: 4a1aca004cf20431c9a66dce85404a6411a54d881a6c257882260ffc972a13eb
Preview script
First 1,000 lines of the extracted script
if (typeof(ADBE.Reader_Value_Asked) == "undefined")
   ADBE.Reader_Value_Asked = false;
if (typeof(ADBE.Viewer_Value_Asked) == "undefined")
   ADBE.Viewer_Value_Asked = false;
if (typeof(ADBE.Reader_Need_Version) == "undefined" || ADBE.Reader_Need_Version < 7.0)
{
   ADBE.Reader_Need_Version = 7.0;
   ADBE.Reader_Value_New_Version_URL = "http://cgi.adobe.com/special/acrobat/update";
   ADBE.SYSINFO = "?p=" + app.platform + "&v=" + app.viewerVersion + "&l=" + app.language + "&c=" + app.viewerType + "&w=" + "XFA1_6";
}
if (typeof(ADBE.Viewer_Need_Version) == "undefined" || ADBE.Viewer_Need_Version < 7.0)
{
   ADBE.Viewer_Need_Version = 7.0;
   ADBE.Viewer_Value_New_Version_URL = "http://cgi.adobe.com/special/acrobat/update";
   ADBE.SYSINFO = "?p=" + app.platform + "&v=" + app.viewerVersion + "&l=" + app.language + "&c=" + app.viewerType + "&w=" + "XFA1_6";
}
javascript_obj0021_001.js pdf-javascript-stream PDF /JS object 21 at offset 0x1C39 2794 bytes
SHA-256: 4e139c8b22ec16bd5aa51575c80dec2bbf89b76977a06b68473031a0eb206366
Preview script
First 1,000 lines of the extracted script
if (typeof(this.ADBE) == "undefined")
   this.ADBE = new Object();
ADBE.LANGUAGE = "ENU";
ADBE.Viewer_string_Title = "Adobe Acrobat";
ADBE.Viewer_string_Update_Desc = "Adobe Interactive Forms Update";
ADBE.Viewer_string_Update_Reader_Desc = "Adobe Reader 7";
ADBE.Reader_string_Need_New_Version_Msg = "This PDF file requires a newer version of Adobe Reader. Press OK to download the latest version or see your system administrator.";
ADBE.Viewer_Form_string_Reader_601 = "This PDF form requires a newer version of Adobe Reader. Although the form may appear to work properly, some elements may function improperly or may not appear at all. Press OK to initiate an online update or see your system administrator.";
ADBE.Viewer_Form_string_Reader_Older = "This PDF form requires a newer version of Adobe Reader. Although the form may appear to work properly, some elements may function improperly or may not appear at all. Press OK for online download information or see your system administrator.";
ADBE.Viewer_Form_string_Viewer_601 = "This PDF form requires a newer version of Adobe Acrobat. Although the form may appear to work properly, some elements may function improperly or may not appear at all. Press OK to initiate an online update or see your system administrator.";
ADBE.Viewer_Form_string_Viewer_60 = "This PDF form requires a newer version of Adobe Acrobat. Although the form may appear to work properly, some elements may function improperly or may not appear at all. For more information please copy the following URL (CTRL+C on Win, Command-C on Mac) and paste into your browser or see your system administrator.";
ADBE.Viewer_Form_string_Viewer_Older = "This PDF requires a newer version of Acrobat. Copy this URL and paste into your browser or see your sys admin.";
ADBE.Viewer_Form_string_Reader_5x = "This PDF form requires a newer version of Adobe Reader. Without a newer version, the form may be displayed, but it might not work properly. Some form elements might not be visible at all. If an internet connection is available, clicking OK will open your browser to a web page where you can obtain the latest version.";
ADBE.Viewer_Form_string_Reader_6_7x = "This PDF form requires a newer version of Adobe Reader. Without a newer version, the form may be displayed, but it might not work properly. Some form elements might not be visible at all. If an internet connection is available, clicking OK will download and install the latest version.";
ADBE.Viewer_Form_string_Viewer_7x = "This PDF form requires a newer version of Adobe Acrobat. Without a newer version, the form may be displayed, but it might not work properly. Some form elements might not be visible at all. If an internet connection is available, clicking OK will download and install the latest version.";
javascript_obj0023_002.js pdf-javascript-stream PDF /JS object 23 at offset 0x1F28 1528 bytes
SHA-256: c876171bd867b66b7671fb337ff9e57d18cd15b43d344cf5a7243821300a408a
Preview script
First 1,000 lines of the extracted script
if (typeof(xfa_installed) == "undefined" || typeof(xfa_version) == "undefined" || xfa_version < 2.0)
{
   if (app.viewerType == "Reader")
   {
      if (ADBE.Reader_Value_Asked != true)
      {
         if (app.viewerVersion < 6.0)
         {
            if (app.alert(ADBE.Viewer_Form_string_Reader_5x, 1, 1) == 1)
               this.getURL(ADBE.Reader_Value_New_Version_URL + ADBE.SYSINFO, false);
            ADBE.Reader_Value_Asked = true;
         }
         else if (app.viewerVersion < 7.0)
         {
            if (app.alert(ADBE.Viewer_Form_string_Reader_601, 1, 1) == 1)
               app.findComponent({cType:"App", cName:"Reader7", cDesc: ADBE.Viewer_string_Update_Reader_Desc});
            ADBE.Reader_Value_Asked = true;
         }
         else
         {
            if (app.alert(ADBE.Viewer_Form_string_Reader_6_7x, 1, 1) == 1)
               app.findComponent({cType:"Plugin", cName:"XFA", cDesc: ADBE.Viewer_string_Update_Desc});
            ADBE.Reader_Value_Asked = true;
         }
      }
   }
   else
   {
      if (ADBE.Viewer_Value_Asked != true)
      {
         if (app.viewerVersion < 7.0)
            app.response({cQuestion: ADBE.Viewer_Form_string_Viewer_Older, cDefault: ADBE.Viewer_Value_New_Version_URL + ADBE.SYSINFO, cTitle: ADBE.Viewer_string_Title});
         else if (app.alert(ADBE.Viewer_Form_string_Viewer_7x, 1, 1) == 1)
            app.findComponent({cType:"Plugin", cName:"XFA", cDesc: ADBE.Viewer_string_Update_Desc});
         ADBE.Viewer_Value_Asked = true;
      }
   }
}