Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac601368f8ac8d37…

MALICIOUS

PDF

83.0 KB Created: 2021-09-12 17:09:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 226659f92598c10f81893e9a247322d9 SHA-1: e26bda2ba08de2a14353c1655d962d6ceb531434 SHA-256: ac601368f8ac8d37bb6b4e9b7ccafcd71150dde422c847b5b305c51eaf396a3e
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and external URIs. The PDF structure suggests it's a link farm, with numerous links pointing to disposable domains, a common tactic for phishing or malware distribution. The embedded JavaScript likely facilitates the redirection or payload delivery, contributing to the exploitation for client execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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 http://banquat.com/userfiles/files/94056495234.pdf In PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/19440081598.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/tivetek.pdfIn PDF document text
    • http://www.erealitysolutions.com/tennisontario/assets/appsadmin/js/ckfinder/userfiles/files/52660570563.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210911021617.pdfIn PDF document text
    • http://beergolfers.com/blog/images/file/50276082778.pdfIn PDF document text
    • https://consurs.ro/ckfinder/userfiles/files/88530276306.pdfIn PDF document text
    • https://jasmijnbloemengroen.nl/userfiles/file/47072001471.pdfIn PDF document text
    • https://zippy-inc.com/app/webroot/userfiles/files/72935014336.pdfIn PDF document text
    • http://pathtojanna.com/userfiles/files/mibiresalokuzox.pdfIn PDF document text
    • http://khachsansapa.vn/webroot/img/files/zakefoburetunaleto.pdfIn PDF document text
    • http://sk4education.com/ckfinder/userfiles/files/vasabetubexatejasagojud.pdfIn PDF document text
    • http://phuquytravel.com/nguyenvanlinh/files/8856794756.pdfIn PDF document text
    • http://kristiankutschera.de/userfiles/file/31925006308.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/f5ede45bea1f775d71fb15873f0ab9f8/tiposigufemiwo.pdfIn PDF document text
    • http://www.pratikchoudhury.com/fckimages/file/16004964630.pdfIn PDF document text
    • http://35ju.21tg.cn/uploadfile/ckeditor/files/nakug.pdfIn PDF document text
    • https://fuoriscena.eu/file/minifubivivezaxibilika.pdfIn PDF document text
    • http://jysfh.com/upload_fck/file/2021-9-8/20210908105816663053.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f088938a5b---16674532441.pdfIn PDF document text
    • http://pkynfe.net/userfiles/file/kezosigowidamigimila.pdfIn PDF document text
    • http://snieznik.pl/userfiles/file/vuzex.pdfIn PDF document text
    • http://yangpupark.com/uploadfile/files/xogozuwoposirugi.pdfIn PDF document text
    • http://assisdrive.pt/userfiles/file/vaburevideduvepavexoniga.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=qr+code+genesis+valtryekPDF 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_off0000df85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF85 10876 bytes
SHA-256: de0328e9e866474ff2aaf51b970927848d6fb4c0beb592feb0e7a97bfc309f7f
font_01_sfnt_off0000f8aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8AA 17744 bytes
SHA-256: 0a3078bd68f38c6b812d6d89c591bd2bfbeebb92c2d933f87e9d1c86b85ccb5c
font_02_sfnt_off000126fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1