Malicious PDF — malware analysis report

Static analysis result for SHA-256 38ff7cf5c8f65aca…

MALICIOUS

PDF

69.4 KB Created: 2021-10-01 20:02:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 012c5d5488311ded8080e7ed317abb8f SHA-1: 21d77aa7ddfd54db58506390911baea382bf14bb SHA-256: 38ff7cf5c8f65aca4a1288559ae6b4ae944c2f1a217459acf667d3032ec35ff3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm, directing users to numerous distinct and potentially disposable hosts. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the link farm heuristic point towards an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://salonorganica.ru/upload/files/45249131726.pdf In PDF document text
    • http://gopherandsquirrelcontrol.com/admin/images/file/zasuv.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16152a41e803d9---71800500906.pdfIn PDF document text
    • https://iveducentar.com/uploads/assets/file/nelokajubobufuxibadilele.pdfIn PDF document text
    • https://biroestarsa.hu/uploads/file/tupuzovokafobunigivubabu.pdfIn PDF document text
    • http://philboyd.com/dulebe.pdfIn PDF document text
    • http://ilkyoukais.com/Images/Media/files/jilobo.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/8p0qru9u15sfnlrf3ulrt0e7jd/40502055619.pdfIn PDF document text
    • https://pastravariaizvoarelebratiei.ro/images/file/76745916942.pdfIn PDF document text
    • http://shinex-auto.com/userfiles/file/kafuresiratebevezu.pdfIn PDF document text
    • http://basumati.com/app/webroot/ckfinder/userfiles/files/folixuwubewasulizoziwazeb.pdfIn PDF document text
    • http://uts.edu.co/portal/app/ckfinder/userfiles/files/luzetojev.pdfIn PDF document text
    • http://influences-vegetales.eu/assets/Image/files/25355053327.pdfIn PDF document text
    • http://inphilong.com/upload/files/wenepusisemedowot.pdfIn PDF document text
    • https://papersacksfactory.ae/images/bulk_images/files/27940935254.pdfIn PDF document text
    • https://accu-split.com/userfiles/files/35689979349.pdfIn PDF document text
    • http://elliptical-trainers.ru/ckfinder/userfiles/files/14075439078.pdfIn PDF document text
    • http://metafelix.it/userfiles/files/36325798882.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/sufogin.pdfIn PDF document text
    • https://wegofa.com/userfiles/file/xekodafigalinuwuduseb.pdfIn PDF document text
    • https://warsztatgdynia.pl/app/webroot/media/files/62998146733.pdfIn PDF document text
    • https://garnet-medical.com/userfiles/files/fexikegosisikenakojitirul.pdfIn PDF document text
    • http://eggtesting.com/admin/uploads/file/dikige.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=movie+coco+full+moviePDF 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_off0000af5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF5B 16872 bytes
SHA-256: ef49aae1ef747a157ecd6bb8c0c772d89eac4c68a7315d22ac1d8e682b7843a1
font_01_sfnt_off0000d9f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F4 10024 bytes
SHA-256: 4e5c5cc348a3b291fb6c51e2c177d1f1371bbeb2ed9ed0ff83ff961bb1983acc
font_02_sfnt_off0000f039.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF039 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1