Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4b4f8be91bfe600…

MALICIOUS

PDF

83.4 KB Created: 2021-09-13 08:08:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 837348143216e2ff784d6a23f788d19a SHA-1: 8752accc6a3ac47c6cb7e7567e69f5c62460ff0d SHA-256: e4b4f8be91bfe6007f37bc8ac10f81bcdafdf99c84506af41c3f65f1b3d8507c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and numerous external links suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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.
  • 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://zjhywt.com/images/upload/File/2560416021.pdf In PDF document text
    • https://vantainoidia.vn/ci/userfiles/files/bakegiwufukawasax.pdfIn PDF document text
    • http://barahi.com/assets/userfiles/files/bikojejapamatiwumozedud.pdfIn PDF document text
    • https://cyberbirddog.com/userfiles/files/10438488464.pdfIn PDF document text
    • https://clubsecurite.fr/webroot/upload/files/5742158481.pdfIn PDF document text
    • http://www.uc-kushiro.net/images/library/File/23908804707.pdfIn PDF document text
    • https://happy-playground.gr/uploads/_uploads/files/rajagazukeba.pdfIn PDF document text
    • http://diamantina-joaillerie.com/ckfinder/userfiles/files/88046165489.pdfIn PDF document text
    • http://candybeauty.vn/upload/files/50250858116.pdfIn PDF document text
    • http://babyshelter.net/assets/upload/files/39159923817.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/zesirudipejuz.pdfIn PDF document text
    • https://aradovan.com/userfiles/file/40621899858.pdfIn PDF document text
    • https://www.groupe-coelho.fr/ckfinder/userfiles/files/74670325559.pdfIn PDF document text
    • http://mixmarketing.vn/upload/fck/file/23587583026.pdfIn PDF document text
    • https://agatanorek.com/files/file/xolopitadixikikeditav.pdfIn PDF document text
    • https://glaze-metalart.com/upload/files/55511620320.pdfIn PDF document text
    • https://www.burnat-provins.ch/ck/ckfinder/userfiles/files/12313159212.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e693bdca7a---seniviloxakelajub.pdfIn PDF document text
    • https://gites-les-bardots.com/userfiles/file/fujug.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/zaxagabatigeputinura.pdfIn PDF document text
    • http://donauwell.at/userfiles/file/jixeninireda.pdfIn PDF document text
    • http://laboratoriodiprogettazione-ve.it/userfiles/files/47961208764.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/4287ac758f742038842f39c83004a5a7/67631932522.pdfIn PDF document text
    • http://www.mmalappeenranta.com/tiedostot/files/govepi.pdfIn PDF document text
    • http://chip-chup.hu/upload/file/joravuwapezo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=i+have+forgot+my+pattern+lockPDF 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_off0000e224.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE224 10888 bytes
SHA-256: 596a5609cafa25d9740cf8ebc7f6a3187d507400dc9e33b871d961c79a6fc528
font_01_sfnt_off0000fb38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB38 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001134a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1134A 17088 bytes
SHA-256: 696d163e680c88a5095b35ba298f188f52e2c68c48e5b4717438d965117d3bdd