Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b4da1a0cef35cec…

MALICIOUS

PDF

70.6 KB Created: 2021-09-28 02:47:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8dfed0ba742e55e0a4fbadd7253a6b1c SHA-1: 4b0b9a67e877e3540099a39ced977d48d41881e3 SHA-256: 7b4da1a0cef35cecae5cbf2883ce8348f359f5854ea1d2e543c5f23efaf25cd8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites. While no scripts were directly extracted, the PDF structure and its association with compromised sites suggest it's part of a phishing or malware distribution chain, likely leveraging embedded JavaScript for exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://atreve.eu/ubezpiecz/obrazy/file/kukavikoziruzireterema.pdf In PDF document text
    • http://autowagon.it/userfiles/files/xisesuter.pdfIn PDF document text
    • https://franchiseharbor.com/files/files/migesidawezazajunalinobu.pdfIn PDF document text
    • http://inventory-acepipe.com/images/uploads/files/91873827340.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161435382c0461---lajubi.pdfIn PDF document text
    • http://bippex.com/filespath/files/20210917001028.pdfIn PDF document text
    • https://twinscooking.nl/twins/userfiles/file/83062664592.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/nejekodag.pdfIn PDF document text
    • https://conexkarvan.com/cache/fck_files/file/turoze.pdfIn PDF document text
    • http://rencontres-icare.org/userfiles/file/nonuzawunudesowifog.pdfIn PDF document text
    • https://rsebolivia.org/userfiles/file/90989279138.pdfIn PDF document text
    • http://bharatandcompany.in/ckfinder/userfiles/files/40212717828.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/567296750dcbae453dc5c8b058264863/zetiwupipinu.pdfIn PDF document text
    • https://kingdomdatesuae.com/userfiles/files/razukudurenu.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/32419232922.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/f0d54024ffd9d26e9ebaec7a50eaa861/19856816779.pdfIn PDF document text
    • https://biholka.cz/uploades/userfiles/file/43566110793.pdfIn PDF document text
    • http://ghettaetamionarchitetti.it/userfiles/files/73590894127.pdfIn PDF document text
    • https://dermatologie-chamonix.com/userfiles/file/68211158237.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/8767824600.pdfIn PDF document text
    • http://ilkyoukais.com/Images/Media/files/foxuxan.pdfIn PDF document text
    • https://lhorizon.ca/uploadHorizon/file/9626781021.pdfIn PDF document text
    • http://flixgolf.com/ckeditor/ckfinder/userfiles/files/70313602743.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=good+morning+android+alarm+songPDF 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_off0000b2c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2C3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cada.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCADA 10400 bytes
SHA-256: cd17db68f3ffd4fc851fa1a3c612d131f128ac12e9901c911bde30a30b4b3892
font_02_sfnt_off0000e20e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE20E 16776 bytes
SHA-256: 624540306acfb893c5f983ea70b81d339793ad32acd84b8b6656c2e1d37699f4