Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0538e51bb62256d…

MALICIOUS

PDF

74.3 KB Created: 2021-09-20 09:18:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5ece19fbcd5fff395dcccfa0235d8491 SHA-1: 6997e3ba94432239348d6d6aeece908a69423282 SHA-256: f0538e51bb62256db01cdbe82ef1dd70c92830479a0829dbd841f74f905f5cb3
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised WordPress sites, indicating a link farm designed to direct users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://les-dvorik.ru/userfiles/file/misidi.pdf In PDF document text
    • http://haphadoor.com/upload/files/93950703310.pdfIn PDF document text
    • http://peneleos.pl/userfiles/file/34124372120.pdfIn PDF document text
    • https://bk.knu.ac.kr/ckfinder/userfiles/files/95368299762.pdfIn PDF document text
    • https://www.ventisilva.com.br/ckfinder/userfiles/files/dinodozisutame.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138d0c47e3b8---zubogokapibukanigalazuru.pdfIn PDF document text
    • https://topconta.ro/userfiles/file/95389148116.pdfIn PDF document text
    • https://aviatroglo.fr/IMG/file/ziwilunitabuvatabotur.pdfIn PDF document text
    • https://rovetco.com/userfiles/file/xumezodatepubezipilif.pdfIn PDF document text
    • http://podarox.ru/public/files/xokovelerimadaziduxati.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161433d55a18b9---setapafurukasuwe.pdfIn PDF document text
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/25388608124.pdfIn PDF document text
    • http://chiangmai-esc.net/user_img/files/36842057032.pdfIn PDF document text
    • http://baharev76.ru/userfiles/file/jexato.pdfIn PDF document text
    • https://hoatuoi360.vn/uploads/files/lekumajisaw.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/69455405161.pdfIn PDF document text
    • https://tedesco.pl/userfiles/file/80728317601.pdfIn PDF document text
    • http://mrs724.ir/basefile/drtiketcom/files/82804774050.pdfIn PDF document text
    • https://greenlakecruises.com/ckfinder/userfiles/files/33954616309.pdfIn PDF document text
    • http://pkpneu.cz/userfiles/file/69172342457.pdfIn PDF document text
    • https://zivotzaokny.eu/res/file/romosu.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/cd43fe4bfbcae923e4a9c8385e0f3956/tesoro.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=a+level+chemistry+textbook+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_off0000bc17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC17 17376 bytes
SHA-256: c4cda284ca27d15b953199e5f0ec837aa7d97b6596dc0ae04485e7026df68b1d
font_01_sfnt_off0000e9bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000101d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101D2 11112 bytes
SHA-256: 3841f8162ce56ff23a884324062f91ff57d88c83ba8a1c54aa20e7161c73046a