Malicious PDF — malware analysis report

Static analysis result for SHA-256 16e497a536f52175…

MALICIOUS

PDF

95.9 KB Created: 2021-10-11 21:19:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 1dcdda50b6c168951f37c880d6e728f1 SHA-1: 85277a74346ec1b4c13740e7118aa4839f715266 SHA-256: 16e497a536f521759c932a512c0b650f8ae2d773463c5ede7919b6f650b81939
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, with specific heuristics indicating it's a link farm on disposable hosting. The PDF contains numerous embedded URLs pointing to various domains, many of which are unknown or suspicious. While no scripts were explicitly extracted, the PDF structure and the high number of external links suggest it's designed to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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 http://webcertain.asia/contentupload/fckeditorUploads/organization_/file/39636847514.pdf In PDF document text
    • http://kasand.com/userfiles/29720888774.pdfIn PDF document text
    • http://nbnjl.com/userfiles/files/fojevugiw.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/3ofnk38udis50gct577itbcr5u/miwepefiz.pdfIn PDF document text
    • http://glendale.kopanramen.com/uploads/files/78203053380.pdfIn PDF document text
    • http://dennehylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/26643424717.pdfIn PDF document text
    • http://www.hydro-tg.pro/upload/file/84869241878.pdfIn PDF document text
    • https://ourcampuswindow.com/ckfinder/userfiles/files/vowivodesepaj.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/unmq7fpomm08728d36975hrnhg/jivegudu.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/6ed023i50qej7lq041ra7ncqef/bonorimuwemerigupebe.pdfIn PDF document text
    • http://thenext.pk/userfiles/files/jelarijukax.pdfIn PDF document text
    • http://morebricks.com/ckfinder/userfiles/files/bidatutotopak.pdfIn PDF document text
    • https://xn--80aaijz0c.xn--p1ai/ckfinder/userfiles/files/jipewekuxufawewop.pdfIn PDF document text
    • https://elearning-chemistry.ro/userfiles/file/kapukawesuw.pdfIn PDF document text
    • http://dui-antidote.net/images/userfiles/file/wevujusarupo.pdfIn PDF document text
    • https://kenhquangcao.vn/uploads/files/novufokez.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/59466927077.pdfIn PDF document text
    • http://theofficeplus.com/userfiles/file/sufumijuxusuwaxed.pdfIn PDF document text
    • http://pttaccounting.com/userfiles/files/jutuba.pdfIn PDF document text
    • http://murito.fr/ckfinder/userfiles/files/duvopujipifokewiwujadi.pdfIn PDF document text
    • http://zoekidsworld.com/userfiles/file/zupusutatuv.pdfIn PDF document text
    • http://nb-magnet.com/upload/files/71370565489.pdfIn PDF document text
    • https://girl0229960192.com/upload/users/files/93975928474.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/BcFPVxLj4jw/uplcv?utm_term=ftse+100+top+fallersPDF 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_off00010b48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B48 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001235a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1235A 21008 bytes
SHA-256: 679a629c408dd8b6dcf3f344b43e450c0bd0247504a12e9b31cd31a89396662e
font_02_sfnt_off00015a57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A57 10308 bytes
SHA-256: 625c407e0c9f4d60b2eb9e6dbfc2a6343014adb75a8497a5679d57518cefc1fa