Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3512d34c83259b2…

MALICIOUS

PDF

83.6 KB Created: 2021-09-17 06:19:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ce0720a442963891d9420bad0946daf8 SHA-1: 3645078cd283ff1b96115ac552a24a34b7c28d0e SHA-256: c3512d34c83259b2a74dde6dd5dd7f6106314d2873fe597dc65daa2e609d830a
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059 Command and Scripting Interpreter T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains multiple embedded URLs, many of which point to PDF files on unknown domains, suggesting a link farm or distribution network. A critical heuristic indicates a 'Clipboard command execution lure,' suggesting the document instructs the user to copy and paste commands into a shell, a common technique for executing malware. The presence of these elements strongly indicates a phishing or malware delivery attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • 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://pozitron-s.ru/userfiles/file/gexufexodujeb.pdf In PDF document text
    • http://ultrabeauty-ff.ru/userfiles/file/gelabetepugerulisew.pdfIn PDF document text
    • http://maximaviajes.com/FCKfiles/file/fomipipu.pdfIn PDF document text
    • http://orthodoxnews.us/file/1962528048.pdfIn PDF document text
    • http://kusistoconstruction.com/userfiles/file/fagenod.pdfIn PDF document text
    • http://dongshengcable.com/images/upload/File/nonisasefu.pdfIn PDF document text
    • http://laclonghotel.vn/upload/files/66500941293.pdfIn PDF document text
    • https://kaptenhoki.info/contents/files/74354155441.pdfIn PDF document text
    • https://cli-kh.com/uploads/files/202109042043196860.pdfIn PDF document text
    • https://yptea.com/data/fckeditor/files/34183606600.pdfIn PDF document text
    • https://www.artikel238.nl/emmwebbit/resources/ckfinder/userfiles/files/19970709363.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ffc26a4aee---43304975906.pdfIn PDF document text
    • https://www.acta-mobilier.fr/ckfinder/userfiles/files/naxenanefo.pdfIn PDF document text
    • http://daiichihr.com/uploads/news_file/dodiginavefimazezo.pdfIn PDF document text
    • https://prestinireedcorp.com/userfiles/files/xakawok.pdfIn PDF document text
    • https://verandapattaya.com/userfiles/files/xozebipexibapulini.pdfIn PDF document text
    • http://cdn.eagle.mn/uploads/userfiles/files/61249428723.pdfIn PDF document text
    • http://vertex-decor.com/userfiles/file/81947006039.pdfIn PDF document text
    • http://mmsmarin.com/imgimage/file/67899002486.pdfIn PDF document text
    • https://classconnbio.com/img-jacson/files/91517574313.pdfIn PDF document text
    • http://xn----7sbicwad4afgcgd5aph7d5e.xn--p1ai/ckfinder/userfiles/files/jowatatif.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/zeweruzisig.pdfIn PDF document text
    • http://ebus.cn/up_file/file/10265686745.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/54a2b7708f87d0b464566994d62c20ba/14057276501.pdfIn PDF document text
    • http://studiocastigli.eu/userfiles/files/xuxutojivewesuwazukeni.pdfIn PDF document text
    • https://cardolf.ro/files/12311643479.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=get+out+download+torrentPDF 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_off0000e122.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE122 10204 bytes
SHA-256: d5a43245a7d76289f29f13fb8089880582be3345e3f9b1a6735b7b09122199a2
font_01_sfnt_off0000f83c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF83C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001104e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1104E 19432 bytes
SHA-256: 2c27bec99a63969ebd2e26afc650b6e8291f56ec744a46051cc2f6d296d751b7