Malicious PDF — malware analysis report

Static analysis result for SHA-256 b983a1eba4132f1b…

MALICIOUS

PDF

87.9 KB Created: 2021-09-22 14:51:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f4de61dadf643d6b48190bd7418a8b2d SHA-1: 80a089f86648d448fcb00927757bb1e8bcfed823 SHA-256: b983a1eba4132f1b89053db63d85ab3ce905e91cebc3a9a04815f422a64c1c0f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with one heuristic identifying it as a link farm on disposable hosting. ClamAV and an ML classifier flagged the PDF as malicious, specifically as a phishing trojan. While no scripts were explicitly extracted, the presence of external URIs and the overall detection suggest an attempt to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://oniceh.ru/uplcv?utm_term=games+naruto+android PDF link annotation
    • http://adec-interiors.net/Uploads/file/gunavitobifer.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137d349146de---zukugo.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/sumema.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/58542800067.pdfIn PDF document text
    • http://emusicmarket.com/upfile/board/files/xepilenezoz.pdfIn PDF document text
    • http://apartmany.cucoriedka.sk/data/files/mifiropekuluzoxiduk.pdfIn PDF document text
    • https://etevent.itweald.com/uploads/files/61404ab5cfe5d.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/41162276694.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/65510304224.pdfIn PDF document text
    • https://nucamsa.es/userfiles/files/74502384780.pdfIn PDF document text
    • https://xlspandoek.nl/userfiles/file/zuvejasozalubu.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/df8f8ae17886130cf008a00e1aa54516/17443649806.pdfIn PDF document text
    • http://www.tsahimmongol.com/uploads/images/files/78600077015.pdfIn PDF document text
    • http://bigdoughpizza.com/uploads/files/35213041918.pdfIn PDF document text
    • https://parc-hotel.info/file/piwiloja.pdfIn PDF document text
    • http://olsztyntransportmedyczny.pl/userfiles/file/gexewovomukabotilubuvufe.pdfIn PDF document text
    • http://swissies.lt/ckfinder/userfiles/files/salixesanonunasumu.pdfIn PDF document text
    • https://dunaweb.co/bg_image/files/62969757251.pdfIn PDF document text
    • http://designbeginnings.com/upload/file/4792367506.pdfIn PDF document text
    • http://nghiencuuykhoa.com/uploads/userfiles/file/76925429625.pdfIn PDF document text
    • http://dharkaninternational.com/survey/userfiles/files/rajedifevituburulavopat.pdfIn PDF document text
    • http://ozkayalartrans.com/userfiles/file/71901865562.pdfIn PDF document text
    • http://cmtl.in/uploads/userfiles/file/file/60605750518.pdfIn PDF document text
    • http://jmyhship.com/uploadfile/files/64017767207.pdfIn PDF document text
    • http://hkacca.com/userfiles/14751627760.pdfIn PDF document text
    • http://ksklinika.ru/ckfinder/userfiles/files/zefikogupidaxupatibegesal.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_off0000f682.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF682 10504 bytes
SHA-256: 4233449227b7cd029a8f3fb2a87c5cf0ae2c0b57811d21d69e72df8d2d4331b2
font_01_sfnt_off00010e64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E64 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012676.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12676 16904 bytes
SHA-256: 130b7c0f7a88bdae1af798ae7a3e06aaba9694f8fc58aad165c9046a60ed75df