Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1d9944c6d77fc35…

MALICIOUS

PDF

68.4 KB Created: 2021-09-29 11:58:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 190da9a4e12179b35bf34d4ae6932c20 SHA-1: 6f6776e8e14986701ef90ea29970f823abc177db SHA-256: a1d9944c6d77fc35f275ea36c7c49ec43bcc53cf45d5f05ed588231faeec79bd
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV and an ML classifier as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting. The embedded URLs are designed to lure users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://shop-exclusive.cz/userfiles/file/tipilebaramonunaretibarop.pdf In PDF document text
    • http://builderall.info/userfiles/file/4104228527.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1613a02ce074a5---poveweteduramuwelot.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131838e50b25---jopepanawejotavobemiwom.pdfIn PDF document text
    • http://integrotech.com/zdjecia/file/88333106609.pdfIn PDF document text
    • http://rosabaum.de/web/editor/files/kepijinuxejaw.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614cd99e33b15---fezadegeraxipexalorax.pdfIn PDF document text
    • https://ingatlansos.hu/images/userfiles/file/pojitisubibuvut.pdfIn PDF document text
    • https://bushregenerators.biz/userfiles/files/fikanerululuv.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/96691269399.pdfIn PDF document text
    • http://www.mmd.ntou.edu.tw/ckfinder/userfiles/files/bavakawo.pdfIn PDF document text
    • https://qwert5.com/psum/admin/userfiles/file/wujozewetisad.pdfIn PDF document text
    • https://www.benkorner.nl/admin/library/ckfinder/userfiles/files/56856630787.pdfIn PDF document text
    • https://coastalholidayproperty.com/ckfinder/userfiles/files/keminabixoz.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/384501f491e7d48012ec26dee463cc95/lixone.pdfIn PDF document text
    • https://bike-accessories.supersites.gr/content/ckfinder/files/51954988201.pdfIn PDF document text
    • http://cjmfgx.morefriendship.com/upload/files/romegug.pdfIn PDF document text
    • http://civicwomen.com/ckfiles/files/19063175551.pdfIn PDF document text
    • https://alsultantrading.ae/userfiles/files/bekuvilovorojoko.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/70685750142.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/38q02uljof0gqq7sc5vnl870nq/71632533460.pdfIn PDF document text
    • http://profil-metall.de/content/uploads/file/nasifimusurusimaluko.pdfIn PDF document text
    • http://harckocsik.hu/userfiles/file/48328178576.pdfIn PDF document text
    • http://okna-stv.ru/userfiles/files/dadixenerapa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=little+women+gomoviesPDF 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_off0000af62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF62 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c779.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC779 10300 bytes
SHA-256: db6d3b4555538a36e28773b1ae4f215274a9acff1623cbb0d2929a322590eabf
font_02_sfnt_off0000deac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEAC 15000 bytes
SHA-256: ffee99778029b4fe76f25543559274bb813b225fd52b47645d473f656db02069