Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4f74bb4f3370db1…

MALICIOUS

PDF

73.6 KB Created: 2021-09-13 19:31:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3fad690847b838c345c72226509bdeca SHA-1: 7d7bf89f77a5f16685355160cf2201387affe1ed SHA-256: f4f74bb4f3370db1ade15249a59f237eae63b1665262dd5cc8cc45adf59fbcb0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to host numerous links, pointing towards a phishing or malware distribution scheme. Although no scripts were extracted, the embedded URLs and the nature of the heuristics strongly suggest an attempt to redirect users to malicious sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://gutachterbewertung.de/userfiles/file/17226306636.pdf In PDF document text
    • http://startent.ru/SITE/files/editor/file/31324611894.pdfIn PDF document text
    • http://smalternatywa.pl/media/upload/files/4cb36f0abdc8de38fcd805c01744b9d9.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1613df0301f4b8---sebarokexi.pdfIn PDF document text
    • http://mc-opony.pl/files/file/senobawolodafi.pdfIn PDF document text
    • http://csc-0898.com/userfiles/file/20210902164727_1h98vs.pdfIn PDF document text
    • http://thuexedanang247.com/uploads/image/files/wadow.pdfIn PDF document text
    • http://salocchi.it/userfiles/files/59530128723.pdfIn PDF document text
    • http://crystaltrade.hu/data/file/fedufurerimodakepalebum.pdfIn PDF document text
    • http://artanuji.ge/admin/ckeditor/ckfinder/userfiles/files/puxugirajelakisika.pdfIn PDF document text
    • http://letdentalab.com/img/files/24665329155.pdfIn PDF document text
    • http://freeski.hu/freeski/file/sewoxasorufikeganome.pdfIn PDF document text
    • http://associazionemillesogni.it/userfiles/files/45253747935.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/robodilafemiwaxira.pdfIn PDF document text
    • http://gruppocreta.com/userfiles/files/sivibaw.pdfIn PDF document text
    • http://wpchkg.com/upload/image/file/20079037669.pdfIn PDF document text
    • http://www.its-dph.cz/admin/fckeditor/editor/userfiles/file/pinagun.pdfIn PDF document text
    • https://slezanie.eu/userfiles/file/99011354294.pdfIn PDF document text
    • http://bilafafafa.com/shopadmin/upload/files/73934940692.pdfIn PDF document text
    • http://themetamorphoseprogram.com/userfiles/file/xebegujijevetiledi.pdfIn PDF document text
    • http://gesundezellen.com/neu/userfiles/file/jizerimadelobovabogadeg.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/elpjgi087ah8bkg6t3a3enl5j2/78002097064.pdfIn PDF document text
    • http://bbmeti.it/userfiles/files/xepilibeguwulowi.pdfIn PDF document text
    • http://chamdure.com/DATA/files/julufawosoriduropixiva.pdfIn PDF document text
    • http://ei-windykacja.pl/upload/file/61104754877.pdfIn PDF document text
    • http://tw-echen.com/uploads/files/202109040755129736.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=catwalk+beauty+mod+apkPDF 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_off0000bd9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD9F 10652 bytes
SHA-256: a83a6f161f1d7cd81b7e7580ded6e08a1abfb4635bdb6bfad8c248c7eb00b0f7
font_01_sfnt_off0000d5e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E8 16496 bytes
SHA-256: 998dd580f8edc95ec429fa4330ff7a5721e5145e7aa0b1a59212b00295205445
font_02_sfnt_off0001007f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1007F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1