Malicious PDF — malware analysis report

Static analysis result for SHA-256 77af0d5bb799f638…

MALICIOUS

PDF

73.5 KB Created: 2021-09-03 19:01:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 643be73e9ca55190bd34b0e1f9657d86 SHA-1: 81b06c4701f4b110ef18018cc3964ec95431b3ca SHA-256: 77af0d5bb799f63897b58104bdf0443dbcdbc0a9882d6ac1f070d9a477c65ad5
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 compromised or disposable hosting domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links. The file's structure and numerous external links align with techniques used to lure victims into visiting malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://mariekevanvlierden.nl/survey/userfiles/files/74324693865.pdf In PDF document text
    • http://msamerica.net/clients/873634/File/16027384864.pdfIn PDF document text
    • http://gianphoiduyloimodel.com/Images_upload/files/nevavunogasoje.pdfIn PDF document text
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/34660236550.pdfIn PDF document text
    • http://alexanderkanevskyartgallery.com/clientMedia/file/59111622736.pdfIn PDF document text
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/15719133934.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b2b7c74b2---42649344654.pdfIn PDF document text
    • http://jlm-kg.com/uploads/file/17468391388.pdfIn PDF document text
    • http://velo.hu/UserFiles//file/98589769544.pdfIn PDF document text
    • http://easyreturn.store/userfiles/file/10904437767.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/34654937147.pdfIn PDF document text
    • http://aliguoriarchitetto.eu/userfiles/files/nuvetawejuxomusum.pdfIn PDF document text
    • http://travisreunion.com/clients/1/1d/1d9c560ef9ee6310b862f4c9d288d7bd/File/17653502509.pdfIn PDF document text
    • http://tai-yang.tw/taiyang/upload/file/lefutet.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/82s0qmd0c9ar0vg4tausjqjq9o/tipikomibifimivijupopor.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/8f4c4629259903b37f701a06b5ea7c34/84043902161.pdfIn PDF document text
    • http://ghettaetamionarchitetti.it/userfiles/files/39048504524.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/0767ff865750f4646081439988ae8b53/pufijupub.pdfIn PDF document text
    • https://tlproduct.com/userfiles/file/79942271967.pdfIn PDF document text
    • http://puzynowska-kancelaria.com/userfiles/file/votumevagarixebabinu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=mustn%27t+or+don%27t+have+to+worksheetPDF 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_off0000bc8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC8E 17112 bytes
SHA-256: 0197bbd4e8cd5290a93fdd68d256f3df79fc0337fb5027dc1febb5e48b6a086e
font_01_sfnt_off0000e853.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE853 10576 bytes
SHA-256: c1a5204880ff3b32ce5dc75856e1307034d3d52282f839bccaf38b7e30134640
font_02_sfnt_off00010093.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10093 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1