Malicious PDF — malware analysis report

Static analysis result for SHA-256 acb4ac0144d9438c…

MALICIOUS

PDF

710.5 KB Created: 2006-04-13 14:44:54 -04:00 Authoring application: Adobe Designer 7.0 First seen: 2018-03-04
MD5: bbab3fd24ef733f172094c658859a136 SHA-1: 8f60eec734d6b284cced34fe52541c9a12e7ad42 SHA-256: acb4ac0144d9438cf0a52750f371a6937c40cc1eda293e3f2c6ae369e7292b9b
94 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains multiple embedded JavaScript streams, indicating an attempt to execute malicious code upon opening. The ML classifier strongly suggests maliciousness. The presence of JavaScript actions and embedded files points towards a downloader or exploit delivery mechanism. The document body is heavily obfuscated and unreadable, providing no further context on the lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8883

Heuristics 8

  • Unusually high stream count medium PDF_MANY_STREAMS
    PDF contains 501+ stream objects — may indicate heap spray or heavy obfuscation
  • 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.
  • 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
  • PDF paints image(s) but contains no text operators info PDF_IMAGE_ONLY_LURE
    PDF has 2 image XObject(s) and the content stream contains no text-emitting operators (BT/ET, Tj, TJ, ', ") in either raw bytes or decompressed streams — this is the screenshot-as-PDF pattern used to bypass text-based scanners and to deliver instructions purely through rendered pixels. It is informational unless paired with invisible links or risky URI context.
  • 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.monotype.comMonotype Referenced by PDF JavaScript
    • 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.monotype.com/html/mtname/ms_arial.htmlhttp://www.monotype.com/html/mtname/ms_welcome.htmlhttp://www.monotype.com/html/type/license.htmlReferenced by PDF JavaScript
    • http://ns.adobe.com/xdp/Referenced by PDF JavaScript
    • http://www.xfa.org/schema/xci/1.0/Referenced by PDF JavaScript
    • http://www.xfa.org/schema/xfa-template/2.2/Referenced by PDF JavaScript
    • http://www.w3.org/1999/xhtmlReferenced by PDF JavaScript
    • http://www.xfa.org/schema/xfa-data/1.0/Referenced by PDF JavaScript
    • http://www.xfa.org/schema/xfa-template/2.1/Referenced by PDF JavaScript
    • http://ns.adobe.com/xfdf/In PDF document text

Extracted artifacts 12

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj1921.bin pdf-embedded-file PDF EmbeddedFile object 1921 at offset 0x9F634 85 bytes
SHA-256: c06dcd026a7ea0536b63e07ce688691b585339a3ab7ff59065e546b56308c7bb
embedded_file_obj1922.bin pdf-embedded-file PDF EmbeddedFile object 1922 at offset 0x9F6E8 1406 bytes
SHA-256: 48346ec364eae4f82597557c8ee633d44dc3ead14d089d50c84db8890206a456
embedded_file_obj1923.bin pdf-embedded-file PDF EmbeddedFile object 1923 at offset 0x9F993 326409 bytes
SHA-256: bb956e1e9cef43350c01af0e8f2010ff0cb132654996ba0ec9ee4e91c470508a
embedded_file_obj1924.bin pdf-embedded-file PDF EmbeddedFile object 1924 at offset 0xA70B9 5196 bytes
SHA-256: 44fb8ebf9d29e8f0734a312b07edd7e559e406b9916e36200fab4e69ef3aed95
embedded_file_obj1925.bin pdf-embedded-file PDF EmbeddedFile object 1925 at offset 0xA71CF 724 bytes
SHA-256: 61642dc7cd003f413c4fa081fa3bbed91086d153eca3840f65c4fb2640556985
embedded_file_obj1926.bin pdf-embedded-file PDF EmbeddedFile object 1926 at offset 0xA73B1 85 bytes
SHA-256: a60265344cf1a9e94da34c8f587f64a4297e2fa417c895852209903ab7588bcc
javascript_obj1913_000.js pdf-javascript-stream PDF /JS object 1913 at offset 0x9EE9D 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_obj1915_001.js pdf-javascript-stream PDF /JS object 1915 at offset 0x9F027 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_obj1917_002.js pdf-javascript-stream PDF /JS object 1917 at offset 0x9F31C 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;
      }
   }
}
stream_008_off00004b32.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4B32 293120 bytes
SHA-256: 3463cb6a96f307e7e3d7300dfb47d1a354c957c464dadd2539dcb8dc271d2635
stream_010_off00030f61.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x30F61 308015 bytes
SHA-256: 4735e29f6b4dfaae31ceba3a66c7548a579b3b0ad8f9ec68bc6e90b0597d7de3
font_00_cff_off00081cda.bin pdf-font-stream PDF embedded font (cff) at offset 0x81CDA 31178 bytes
SHA-256: 23831e143e2e1a484b95ee765b15d94562c951468b895c080e655667dc04ddf0