Malicious PDF — malware analysis report

Static analysis result for SHA-256 b291753e39adf299…

MALICIOUS

PDF

72.0 KB Created: 2021-09-08 10:09:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 85ec46378c46916acca79e1292fb7da3 SHA-1: 278d87753f99a3bac90de4b040232043119d8831 SHA-256: b291753e39adf299dee2cf3082c015329f84908f497704656ee5e61215ebe99a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is identified as a malicious PDF by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external URIs, many of which point to compromised websites or link farms, suggesting an attempt to redirect users to malicious content. The PDF structure and embedded JavaScript indicate it's likely used as a lure to download further payloads or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://plovdivweek.com/app/templates/js/ckfinder/userfiles/files/zowanuxifogawodu.pdf In PDF document text
    • https://imagebeaute.fr/userfiles/file/4247114935.pdfIn PDF document text
    • https://gulyaskantin.hu/uploads/frontend/files/90217467336.pdfIn PDF document text
    • http://www.motionmantra.com/userfiles/files/wijudezuzavazaxa.pdfIn PDF document text
    • http://www.moyekolodin.com/files/10232950859.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/tajag.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/0re0o4dmrj3m62rkl6najaqviu/bojawukobonedoga.pdfIn PDF document text
    • http://schmetterlingsgaerten.de/file/vobewad.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b3d3b8287cb---zebovidojuva.pdfIn PDF document text
    • http://lltsg.com/uploadfile/file///2021081622191937.pdfIn PDF document text
    • http://dmhfamilyreunion.com/clients/4/44/44eff64e497b984d8b2945277059c9c0/File/36173809529.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/dve6t74t2oh75e2vm0vom724r7/92808877279.pdfIn PDF document text
    • http://droprint.my/home/ququ4923/public_html/userfiles/file/natakap.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/4670895d4efc3d94d030284f01fb3f4e/jenezewakuraxulixomek.pdfIn PDF document text
    • http://zerosquareonline.com/file/vafoxulamobigez.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/de7cab97d367ffd5b3cecd8757374813/porutonebojer.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/nafajezezoretufo.pdfIn PDF document text
    • http://gildiamasterov.ru/userfiles/file/vevanonuvu.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/vutijajerolaked.pdfIn PDF document text
    • http://kleiberit.ru/files/file/71226176636.pdfIn PDF document text
    • http://brilliantsolarpaneling.com/userfiles/file/45075600250.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=english+file+intermediate+third+edition+workbook+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#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://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b5e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5E4 16644 bytes
SHA-256: 757da3c85683b9d0cf1265241b8bda266e3fc336262edd7655c22a108d097799
font_01_sfnt_off0000e070.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE070 11244 bytes
SHA-256: 919e8b397b4bf1bdea9c1043e55a0801b0ccab867217d664431756899987ea35
font_02_sfnt_off0000fa2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA2F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1