Malicious PDF — malware analysis report

Static analysis result for SHA-256 021fe0dec85a6287…

MALICIOUS

PDF

76.0 KB Created: 2021-09-24 00:51:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 706f46bc16d1e1ff4d935004ba3e7e6f SHA-1: 4cdaae28324f3f463a5b81428434ffaae7442d1b SHA-256: 021fe0dec85a62873269973d05501fc0b4fa6dd96fe42563b013b9a6edfb3c8e
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 for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. The presence of numerous external URIs, many on disposable hosting, strongly suggests a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and the nature of the URLs point towards a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://synerhu.ru/uplcv?utm_term=proficiency+expert+coursebook+key PDF link annotation
    • https://alixdemassy.fr/userfiles/file/88468538962.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/65623858604.pdfIn PDF document text
    • https://loyalangkorapartment.com/userfiles/file/pifuwugan.pdfIn PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/zirafesosegesaj.pdfIn PDF document text
    • https://lyna-garage.com/htdocs/cljr/data/files/10709788667.pdfIn PDF document text
    • https://kalimati.in/userfiles/file/71475976594.pdfIn PDF document text
    • http://tsnpharma.com/upload/files/tasekemili.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/vuzugejagawunebe.pdfIn PDF document text
    • https://mediaskills.rs/files/bafukanekamalegikumib.pdfIn PDF document text
    • https://manajrgvaaradhi.com/cms-uploads/files/suzuxogupan.pdfIn PDF document text
    • http://kooijobs.in/ckfinder/userfiles/files/luxerubifiwatupazujoxal.pdfIn PDF document text
    • http://punaide.com/userfiles/files/pulupovepejirak.pdfIn PDF document text
    • https://clubelsendero.com/img_pag/file/supudupasomewu.pdfIn PDF document text
    • https://doanhnghiepvietnam.niengiamdoanhnghiep.vn/img_duhoc/files/xolubobokanijudozifozo.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/nijabefonerizu.pdfIn PDF document text
    • http://asiancfea.org/userfiles/file/xopajojeg.pdfIn PDF document text
    • http://kangmeideyiliao.com/uploadfile/file///2021090207171854.pdfIn PDF document text
    • http://inphilong.com/upload/files/55795409827.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c6db259159---21539177504.pdfIn PDF document text
    • http://dekogard.net/deko/veri/_files/628644017.pdfIn PDF document text
    • http://alde-pace.org/ckfinder/userfiles/files/14006497354.pdfIn PDF document text
    • http://mvpbuilding.com/userfiles/file/25394134685.pdfIn PDF document text
    • https://lazerom.pro/media/file/lataridodidejisibafezi.pdfIn PDF document text
    • http://zima.italie-ubytovani.cz/data/file/zitubeda.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_off0000bfa3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFA3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d7b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7B5 19028 bytes
SHA-256: 9a580652a8441dacc8ecc0898e1af362ef052154350898d0a5b79c8691e2c189
font_02_sfnt_off000109b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109B1 10816 bytes
SHA-256: 9ec32506c4b4f5d1e37566650d3bb8912eecccf71769914084d4765e03004a9c