Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3c9aa9d0cff8299…

MALICIOUS

PDF

92.3 KB Created: 2021-09-18 07:13:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d64c692dad37f8c9ad94e074c10d4a22 SHA-1: 741f6e712b787784fc25772f64f35ad2303e5404 SHA-256: c3c9aa9d0cff829966717c2c7858e0e2a478ffcc6f71829aae05d6e361383fb6
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple external links, with one identified as a random URL on potentially disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://pixomot.ru/uplcv?utm_term=the+walking+dead+season+5+full+episodes PDF link annotation
    • https://gornjastubica.hr/files/rowowuxibuvavez.pdfIn PDF document text
    • https://aadharshilaschool.org/userfiles/file/76011094205.pdfIn PDF document text
    • https://biocenfis.es/uploads/assets/file/taporelufaruzifogeb.pdfIn PDF document text
    • https://lecachet.fr/docs/files/budakerekibibugug.pdfIn PDF document text
    • https://angkagenap.com/contents/files/tozazodefakidezurenufevon.pdfIn PDF document text
    • http://arndt-fahrschule.de/userfiles/file/80885880461.pdfIn PDF document text
    • http://baschin-heizung.de/meineBilderAlbertGrundschule/file/nopizo.pdfIn PDF document text
    • https://szabobuszberles.hu/files/files/towujaredi.pdfIn PDF document text
    • https://alirezamirmohammadi.com/images/upload/files/23651871326.pdfIn PDF document text
    • http://www.iciparis.ru/ckfinder/userfiles/files/69200860266.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/e16ba33d1bb8dafaa6e4616b05ca1b30/21477539922.pdfIn PDF document text
    • http://lucidarepavimentimarmogenovaealessandria.it/userfiles/files/36805187906.pdfIn PDF document text
    • http://imdmotors.com/uploadfile/file/2021091007431749.pdfIn PDF document text
    • https://thepainter.asia/upload/files/95321832273.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/161367fe361ab0---wurewonubeguporumudonug.pdfIn PDF document text
    • http://herborgthailand.com/file_media/file_image/file/zajafifojax.pdfIn PDF document text
    • http://pneusmarene.it/images/file/8845827704.pdfIn PDF document text
    • http://manchetenewsms.com.br/ckfinder/userfiles/files/91190457553.pdfIn PDF document text
    • http://intelekt.biz/uploads/pages/files/3351825744.pdfIn PDF document text
    • https://guanlai.tw/uploads/files/202109131504134015.pdfIn PDF document text
    • http://rorolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/91323105648.pdfIn PDF document text
    • http://xn----7sbbgprpk7biiq.xn--p1ai/admin/ckfinder/userfiles/files/33835798716.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/buwikiv.pdfIn PDF document text
    • http://k9careclinic.in/ckeditor/ckfinder/userfiles/files/27167988861.pdfIn PDF document text
    • http://upakuika.com/img/file/74283422495.pdfIn PDF document text
    • http://85560891.com/upfolder/e/files/20210906210119.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_off000101c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000119e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119E0 10952 bytes
SHA-256: 3900d9cfdb72ec6d623b9f07dcdfdad2056e090bc584745e384551c48e69ae32
font_02_sfnt_off00013315.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13315 18564 bytes
SHA-256: ab9d85e2d413e24f6b551b5521ce27410b027b287a28f5928d5bba28646d9625