Malicious PDF — malware analysis report

Static analysis result for SHA-256 6de3b8365f9945d1…

MALICIOUS

PDF

72.8 KB Created: 2021-09-18 17:47:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: cb9552f3eec99d17c3d7a616035e9917 SHA-1: 0800cf3ed82db0ecd278f417607b2a0d9f5b4001 SHA-256: 6de3b8365f9945d1fed0855ebfb9c37f5b4e3dd8df64d25c3fec55f99531681a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external sites, suggesting a phishing or malware distribution scheme. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this by indicating the PDF is part of a link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://fusheng-vietnam.vn/admin/webroot/upload/image/files/76344250739.pdf In PDF document text
    • http://muszempilla.com/files/file/58248862526.pdfIn PDF document text
    • http://fluitec.fr/ressource/site-image/files/piwuxidubuwodutebepugixe.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/42276772368.pdfIn PDF document text
    • https://tradegateindia.com/userfiles/file/63269708932.pdfIn PDF document text
    • http://xn----8sbfeahwarn6ac1adp3fb2p.xn--p1ai/userfiles/file/26286991852.pdfIn PDF document text
    • http://xn--80aafbanafwvcftiqfecrg2a.xn--p1ai/pict/file/72396574242.pdfIn PDF document text
    • http://chetaomaynganhnhua.com/uploads/files/28836702495.pdfIn PDF document text
    • http://noithatachau.vn/webroot/img/files/zobomuvolenuroxuroge.pdfIn PDF document text
    • http://austria-ex.com/images/blog/file/41085073296.pdfIn PDF document text
    • http://geometramaurotozzi.it/userfiles/files/4176532121.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/96444239076.pdfIn PDF document text
    • http://sromedical.com/file_media/file_image/file/83280962297.pdfIn PDF document text
    • https://bharatceramics.in/ckfinder/userfiles/files/6178814539.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210912_5255D594F5ABF3D8.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/23752420824.pdfIn PDF document text
    • http://www.logomarcanet.com/userfiles/file/61030814760.pdfIn PDF document text
    • https://allcreaturesinc.com/files/files/76843310750.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/5283040474.pdfIn PDF document text
    • https://interstudy.net/userfiles/file/nanedevi.pdfIn PDF document text
    • http://ilovestory.com/upload/file/80534970771.pdfIn PDF document text
    • http://srub-servis.ru/userfiles/file/50644187663.pdfIn PDF document text
    • http://autosvilar.com/uploads/ckfinder/files/kejup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=datepicker+js+examplePDF 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_off0000b791.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB791 10636 bytes
SHA-256: 91211155a5fad1b569ad11352e7cece0b6b1a2b3035e99d1eadca575b2f9114c
font_01_sfnt_off0000cff4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e806.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE806 17428 bytes
SHA-256: 56771396b7dda9ce7dcef517f19eeb2209879b89285c307e2731dadc3be3e762