Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa9f1e8f369cd4b4…

MALICIOUS

PDF

84.1 KB Created: 2021-09-18 02:09:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 2ac946c8765750b68c005e66cf8346fe SHA-1: 565ef1bf0d5d59acb1f6d18d8b1c67c4e0191898 SHA-256: fa9f1e8f369cd4b4a47775f197272dccd71eec8e0bfc57e6986f627d803406d4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to compromised or disposable hosting. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://dongphat.net/upload/files/zorivigetojibugupozem.pdf In PDF document text
    • http://poslovniimenik.net/firme_data/files/97438598782.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/bowoxatokosos.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134d3be780ad---juvesumixaxexud.pdfIn PDF document text
    • http://lixupeng.com/uploads/files/doxetasadeko.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/pefene.pdfIn PDF document text
    • https://watosaphotography.com/app/webroot/userfiles/files/20210907_235535.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e5c929ee87---70045048263.pdfIn PDF document text
    • https://tattica.byespresso.com/app/webroot/files/upload/files/vutimebazezudavexanobozij.pdfIn PDF document text
    • http://ketoanantamhcm.com/uploads/files/rafaso.pdfIn PDF document text
    • http://franceplus.fr/userfiles/file/35348303537.pdfIn PDF document text
    • https://hainutedecopii.eu/ckfinder/userfiles/files/dolufukibod.pdfIn PDF document text
    • http://carbontuning.ru/file/joduxojiveku.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/jorijekedez.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/161349bb9ee6bd---92671316116.pdfIn PDF document text
    • http://efuegypt.org/userfiles/file/zugowunakijubasavox.pdfIn PDF document text
    • http://www.dean-cpa.com/files/adminpic/file/livuzuserepolusati.pdfIn PDF document text
    • http://mayjack.com/upload/files/xezurumiluvi.pdfIn PDF document text
    • http://cpghollywood.com/userfiles/files/92051457248.pdfIn PDF document text
    • http://newworldss.com/uploads/file/wuzota.pdfIn PDF document text
    • http://77owship.netsociality.com/upload/files/85335612193.pdfIn PDF document text
    • http://floridadressyourhome.com/uploaded_files/userfiles/files/54484467147.pdfIn PDF document text
    • https://psystat.net/candyticket/uploads/page_images/files/63786264391.pdfIn PDF document text
    • http://getdol.com/page_data/file/kewuseja.pdfIn PDF document text
    • http://www.psoevalledeabdalajis.es/ckfinder/userfiles/files/68907378194.pdfIn PDF document text
    • http://lexprikson.com/admin/style/images/userfiles/file/45117364818.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=session+layer+in+osi+modelPDF 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_off0000e585.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE585 17516 bytes
SHA-256: 43b5f3b5f7165aead109fb8eb6dad7be0a6126f453f71c27ec1a3f719ecdcfc2
font_01_sfnt_off0001129a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1129A 10500 bytes
SHA-256: 5f13eb40015c760fca985f30986f8880f5574accad0caf08cedb555b0d61930e
font_02_sfnt_off00012a6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A6F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1