Malicious PDF — malware analysis report

Static analysis result for SHA-256 60a3bd7d62f28573…

MALICIOUS

PDF

73.7 KB Created: 2021-10-08 07:35:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 8f87a69e4499d5e03286fa8f3ef27e4f SHA-1: 6feacc92b223a3478f2f260738e0f9ad21b15554 SHA-256: 60a3bd7d62f285731cd88d11438b3411f08c63da854cb1bf5b1b8fb8095d292e
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 flagged as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple potentially compromised websites hosted on disposable domains. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 6

  • 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.
  • 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 https://www.hsbofmn.com/ckfinder/userfiles/files/levinakulozivad.pdf In PDF document text
    • http://sous-mama.org/userfiles/file/kapigimeginobutemomowek.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/161325655cbcf7---37275604288.pdfIn PDF document text
    • http://getwealthythisyear.com/ckfinder/userfiles/files/zifipuvonuji.pdfIn PDF document text
    • http://deleersnijder-bocaege.be/images/file/pesokunofa.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/xukuzode.pdfIn PDF document text
    • http://laconchigliacasevacanze.it/userfiles/files/gapepamulotatemo.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/79710872147.pdfIn PDF document text
    • https://latgalesamatnieki.lv/files/file/79524752592.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/81934621397.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/8b63bf1e3d25015fa25cac35f1c34e64/3673097842.pdfIn PDF document text
    • https://marosme.ro/hirek/file/42410311823.pdfIn PDF document text
    • http://bluebirdcanada.com/FileData/ckfinder/files/20210908_730604BF343BEDFC.pdfIn PDF document text
    • https://lhorizon.ca/uploadHorizon/file/sirunojo.pdfIn PDF document text
    • https://lhdgv.ca/lpch2010/userfiles/file/wetufibakidimuduvud.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149f3e850993---29389571238.pdfIn PDF document text
    • http://thechelseaff.com/user_uploads/files/ginakaviwasexawusarov.pdfIn PDF document text
    • http://keramann.ru/uploads/files/82406019907.pdfIn PDF document text
    • http://parzenica-bialka.pl/userfiles/files/7869814756.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/sopikexumimubi.pdfIn PDF document text
    • http://pioneerbuzz.net/userimages/pozat.pdfIn PDF document text
    • http://firstcuwire.com/file_media/file_image/file/xalafari.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/52617351061.pdfIn PDF document text
    • https://braus.uz/images/shared/file/ratozuzabi.pdfIn PDF document text
    • http://precedent.by/_newsite/images_from_html_editor/file/mixewuvamukemewubuja.pdfIn PDF document text
    • http://www.sanjuktabanerjee.com/fckimages/file/30502903509.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=php+date+millisecondsPDF 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_off0000b9dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9DD 18120 bytes
SHA-256: 6b99439728a01061ec4df13b55047f3ff93e9eb3a41da2c74cd4d26addeefdca
font_01_sfnt_off0000e8c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8C6 10680 bytes
SHA-256: af874aac1412dbab22b448284a5f20677182a9ac89521729cf27ead53aedb7cf
font_02_sfnt_off00010112.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10112 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1