Malicious PDF — malware analysis report

Static analysis result for SHA-256 16815c9dab2c9b01…

MALICIOUS

PDF

79.2 KB Created: 2021-09-14 13:04:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 6e012ff2f965cdca2bd7dae361bbc736 SHA-1: 23d6b43cd14333383390f9ed627a736fa8f64770 SHA-256: 16815c9dab2c9b015f460464154a0fa47b73260e70d4c44b216019d6724b85e6
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the PDF is structured as a link farm, likely to trick users into clicking through to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://smidgel.ru/uplcv?utm_term=vlc+language+change+app+download PDF link annotation
    • http://otworz-biuro-podrozy.pl/userfiles/file/duvakesapegurusug.pdfIn PDF document text
    • http://hsi-international.com/ckfinder/userfiles/files/51589479363.pdfIn PDF document text
    • http://bogaarchitetti.it/userfiles/files/rutobine.pdfIn PDF document text
    • https://jewfri.kr/files/image/files/68550265500.pdfIn PDF document text
    • https://chezgregoire.fr/userfiles/95667223809.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/210ae871ebe66a70cde5b6e38f2cb15c/jaruputuruzorawanemid.pdfIn PDF document text
    • https://bfull.ru/uploads/files/43805187415.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358238dc2e9---raxefazisibuk.pdfIn PDF document text
    • http://consoles-a-gagner.com/fckeditor/userfiles/file/fotunaladuxojifinif.pdfIn PDF document text
    • https://istanajp2.com/contents/files/72043652767.pdfIn PDF document text
    • http://serextion2006.com/js/upload/files/jemetutijogadotuzubus.pdfIn PDF document text
    • http://ecme.site/2015/vat/upload/files/xopopinuvomupapasubone.pdfIn PDF document text
    • http://pphjako.pl/userfiles/file/gaxibupaxosidam.pdfIn PDF document text
    • http://hyundaihungthinh.com/uploads/images/files/tofegu.pdfIn PDF document text
    • https://vanchuyenduongsat.vn/upload/files/maturelutajozonolerak.pdfIn PDF document text
    • http://www.pavimentosyreformasferlu.es/ckfinder/userfiles/files/sobuval.pdfIn PDF document text
    • https://condominiovillage.com/userfiles/file/bokenekezak.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/kewokax.pdfIn PDF document text
    • http://roomyab.ir/basefile/roomyabir/files/92796926351.pdfIn PDF document text
    • https://fundoohairstyles.com/hairstyler/images/file/57809925494.pdfIn PDF document text
    • http://liqaa-lb.com/files/userfiles/files/kitinizowolivif.pdfIn PDF document text
    • https://robindayne.com/ckfinder/userfiles/files/84828431867.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/lukuto.pdfIn PDF document text
    • http://shangyi-pump.com/uploads/file/09101027739.pdfIn PDF document text
    • http://carsonpokebar.com/uploads/files/50131950495.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_off0000d1f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1F9 17552 bytes
SHA-256: b1c8b5252377ae50fd80dabbf0b5a8416dd6c22e7e27213014fe62d5a9edf37a
font_01_sfnt_off0000ff9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF9A 10488 bytes
SHA-256: ddb5cd4192ab13361bb8c6d2327f2b09c91e7beec8d85826dc36be9e8bf795ec
font_02_sfnt_off0001173e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1173E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1