Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bda8b7c442d5e41…

MALICIOUS

PDF

79.6 KB Created: 2021-09-21 06:11:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 35601761c73ac469707fe1af909dfbc3 SHA-1: 9e1869cfc42d96a68f84939c7b786d80cc3fcb2d SHA-256: 3bda8b7c442d5e410b1841cd1d297cedc936d85c8582b273ec73971b230a29f2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier indicating maliciousness. It contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains, suggesting a phishing or malware distribution scheme. The presence of external URIs and the overall structure point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://archism.ru/uplcv?utm_term=v+graphics+gta+sa+download PDF link annotation
    • http://brezov-gaj.si/uporabnik/file/1732719602.pdfIn PDF document text
    • https://kozhikodedeaf.org/admin/my_files/file/31752329299.pdfIn PDF document text
    • https://glaskunstcentrum.nl/images/file/90352644658.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/39096900123.pdfIn PDF document text
    • http://php-lounge.de/userfiles/file/99529025440.pdfIn PDF document text
    • http://laulumaja.fi/ckfinder/userfiles/files/tirezan.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/bumizududumoxenofelal.pdfIn PDF document text
    • http://antansconstructions.com/ckfinder/userfiles/files/51687575890.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613576c8af3d6---fixozivu.pdfIn PDF document text
    • http://labellebeaute.com.hk/ckfinder/userfiles/files/tawesob.pdfIn PDF document text
    • https://nenmongdangquang.com/upload/files/fivuxol.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.com/userfiles/file/61872127078.pdfIn PDF document text
    • http://wronba.com/uploads/wysiwyg/file/66863318318.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/fetalunomepare.pdfIn PDF document text
    • https://autonoleggioassereto.com/file/55272781788.pdfIn PDF document text
    • https://led7.ru/file/23827620373.pdfIn PDF document text
    • http://xn--80aer5aza.xn--19-kmcm3c.xn--p1ai/ckfinder/userfiles/files/nanokufelizakixipexanimo.pdfIn PDF document text
    • https://www.comperat-89.fr/ckfinder/userfiles/files/kuveruva.pdfIn PDF document text
    • http://jawarakreasi.com/file/64258397893.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613857e1e3809---wovuxapezoro.pdfIn PDF document text
    • https://ooo-kenk.ru/userfiles/file/77999660231.pdfIn PDF document text
    • http://obrienbuilders.com/userfiles/file/8512696895.pdfIn PDF document text
    • https://probidjp.com/ckfinder/userfiles/files/20210920_090805.pdfIn PDF document text
    • 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_off0000d34a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD34A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB5C 17268 bytes
SHA-256: 5d84a4f45eb18ad0a7e972c1b1a52bd8ad5b617290b1bdb64adf59799bffac61
font_02_sfnt_off0001185c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1185C 10716 bytes
SHA-256: fe3a145f61d990e1d8b935d15071c52d3942a3ed6ef4b9ec0b3280ab81b7027b