Malicious PDF — malware analysis report

Static analysis result for SHA-256 8df5f7369b255353…

MALICIOUS

PDF

86.4 KB Created: 2021-09-19 01:45:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 27dfc098212d6e1af201030c1b017b92 SHA-1: a08bdea9b9d3cefede00bd082d5d91136062a337 SHA-256: 8df5f7369b2553537624f510f2f5d8b0012adcd9c73e1d78a39e5e191f00e9b3
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with a critical heuristic firing for PDF_SEO_DISPOSABLE_LINK_FARM. It contains embedded JavaScript, indicating an attempt to execute malicious code. The presence of numerous external URIs, many pointing to disposable domains and forming a link farm, suggests a phishing or malware distribution scheme. The primary attack pattern involves leveraging these links and potentially the embedded script to redirect the user to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://ratodua.com/contents/files/tivufekozugizuj.pdf In PDF document text
    • http://lactopad.com/uploads/files/619978293.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/9e3e944e6253140fafd3cb883df3cd1b/luwelukopuvunu.pdfIn PDF document text
    • http://www.hro.ait.ac.th/js/ckfinder/userfiles/files/37915948534.pdfIn PDF document text
    • https://hanakspotrebice.cz/eshop/ckfinder/userfiles/files/38847932152.pdfIn PDF document text
    • https://iohrp.org/f_files/files/88093422552.pdfIn PDF document text
    • http://wolfpackbasketballacademy.com/content_docs/biluxo.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/98919275991.pdfIn PDF document text
    • http://merlegdoktor.hu/tmp/jevatulaweziturof.pdfIn PDF document text
    • http://phuclocvienjsc.com/uploads/image/files/71557388618.pdfIn PDF document text
    • http://hiniceshine.com/upload/gexenojedapomeg.pdfIn PDF document text
    • http://mrs-edu.com/sribati/editor/uploadfiles/4490722026.pdfIn PDF document text
    • http://elmbbq.com/uploads/files/22428252218.pdfIn PDF document text
    • http://viviapalermo.com/userfiles/files/zijuzixatigupelad.pdfIn PDF document text
    • https://h1t-url12shio-turbo.com/contents/files/zigepenuwuwaposizamili.pdfIn PDF document text
    • https://laundrybyconrads.com/nbloom/fckuploads/file/sibolev.pdfIn PDF document text
    • http://agriturismocorteerbatici.it/userfiles/files/minerudazulikatas.pdfIn PDF document text
    • http://7m-shop.com/userfiles/file/77073574864.pdfIn PDF document text
    • https://fereshtegan.net/basefile/fereshtegannet/files/datugabubola.pdfIn PDF document text
    • http://mp-journal.com/media/file/46710058188.pdfIn PDF document text
    • https://xn--72ca1bzcdf9cg5df4n5a8cei.com/userfiles/files/94782446942.pdfIn PDF document text
    • https://unicorn.mn/js/ckfinder/userfiles/files/vokubukuwizojanot.pdfIn PDF document text
    • https://2-view.org/home/view/public_html/ckfinder/userfiles/files/30477368927.pdfIn PDF document text
    • http://faurau.com/luodan/images/userfiles/file/fejasutiramanarativ.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=best+slot+machine+app+androidPDF 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_off0000ed58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED58 17640 bytes
SHA-256: 805a08578eb28d20801efbb4cace662110504cdb96c03ef5a948b5d023fdd43a
font_01_sfnt_off00011b54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B54 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001336b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1336B 10832 bytes
SHA-256: 0e377613947969913f98139fa88b8fc563ae872810f44cbba59b16b9681ca489