Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6ff4b72299a1c23…

MALICIOUS

PDF

74.1 KB Created: 2021-09-20 02:53:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 73289820dc2a03b231fca27c08774f97 SHA-1: 51249eadca6f789e430137f1220d7135c185081c SHA-256: a6ff4b72299a1c230410a022b6bc39f1c0c81cfdd8d16fee638a51de57f08185
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The PDF also hosts a large number of external URLs, many of which are linked to disposable domains or appear to be part of a link farm, suggesting a phishing or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/73ddef542f8de49e7b363b6dcbbdd9c7/xuvepoduvorakufavijuk.pdf In PDF document text
    • http://www.dilipprabhavalkar.com/images/file/tusubonalimuf.pdfIn PDF document text
    • http://istanbulballoons.com/ckfinder/userfiles/files/nidemowuguwuzap.pdfIn PDF document text
    • http://prmakeup.com/Image/files/2280427793.pdfIn PDF document text
    • https://bibonatura.hu/ckfinder/userfiles/files/69378203276.pdfIn PDF document text
    • https://renebeumer.nl/userfiles/file/mibimulonenoxulatapovudi.pdfIn PDF document text
    • http://xn--80aamwn.xn--p1ai/userfiles/file/34324004384.pdfIn PDF document text
    • https://banerjeetourspecial.in/ckfinder/userfiles/files/52181671100.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/lazamijomuwilodi.pdfIn PDF document text
    • https://maytinhdalat.vn/images/uploads/files/86883802823.pdfIn PDF document text
    • http://maychebiengoduykhuong.com/media/ftp/file/nojexirat.pdfIn PDF document text
    • http://regalmotors-jp.com/js/upload/files/9699445834.pdfIn PDF document text
    • https://worldcastlive.com/userfiles/file/25891019217.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/3669263926.pdfIn PDF document text
    • http://maihome.hu/admin1/file/76971027416.pdfIn PDF document text
    • http://maxgear.cz/webpagebuilder/ckfinder/userfiles/files/xofodozo.pdfIn PDF document text
    • https://atlantidegattico.it/file/refedoziseloxi.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16147bf8d02648---felidaxasotekilaxedoju.pdfIn PDF document text
    • https://mai-avto.ru/upload_files/file/84541234171.pdfIn PDF document text
    • http://cmtl.in/uploads/userfiles/file/file/bitonapira.pdfIn PDF document text
    • http://www.gieskestukadoors.nl/ckfinder/files/files/lanadolawuretadegagu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=hair+salon+near+me+open+on+saturdayPDF 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_off0000bd3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD3C 10756 bytes
SHA-256: e3cf0cae4cc64a516616be3039d149ba08555b2d93141c449b10d480aa30e6b8
font_01_sfnt_off0000d5e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E7 17340 bytes
SHA-256: 2df47e7006a3774f31d29b1a5750ac228c1a7c7197297ad96245b5902bc1ede7
font_02_sfnt_off000102b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1