Malicious PDF — malware analysis report

Static analysis result for SHA-256 98f83e1b3191e945…

MALICIOUS

PDF

82.0 KB Created: 2021-09-17 11:11:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2912202942b8538dd417eb78846c3d8a SHA-1: d63b3d44e6cb2cb8b00ae4d924a8da40166802b5 SHA-256: 98f83e1b3191e9457bfa9975980b3a4bf5be1bf8999153ce4cd83f5dce124df3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Numerous embedded URLs were found, with many pointing to suspicious PDF files on disposable domains, indicating a link farm designed to redirect users. The document body is heavily obfuscated and unreadable, suggesting it is not intended for human consumption but rather to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://implant-drill.com/userfiles/file/26554007886.pdf In PDF document text
    • http://gddfboiler.com/uploads/files/dokoributotijulu.pdfIn PDF document text
    • https://benqmusicworkshop.com/fupload/file/72268049986.pdfIn PDF document text
    • https://mytalk7.com/_UploadFile/Images/file/zekeduwokinedogud.pdfIn PDF document text
    • http://ranch.pl/files/file/66719155912.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/2edafccdfe1e555fda98a2cba259bd4b/72645231752.pdfIn PDF document text
    • http://mibenjamin.com/userfiles/file/26449817256.pdfIn PDF document text
    • http://huanghels.com/filespath/files/20210901183341.pdfIn PDF document text
    • http://gangwonbnb.com/FileData/ckfinder/files/20210903_C6934E107583C1E6.pdfIn PDF document text
    • http://utuin.net/files/fckeditor/file/jugura.pdfIn PDF document text
    • http://zoldjogsi.hu/uploads/files/38458928080.pdfIn PDF document text
    • https://burgas-remonti.com/userfiles/file/26589723908.pdfIn PDF document text
    • http://rogersdesignhouse.com/uploads/files/kulofaluxarewuvebitipamu.pdfIn PDF document text
    • https://its-bulgaria.bg/files/file/xebukogivejumosex.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/zanadovi.pdfIn PDF document text
    • http://budoprojekt.eu/obrazy/file/46822089384.pdfIn PDF document text
    • https://batdongsandothanh.vn/luutru/files/16766801858.pdfIn PDF document text
    • http://bidwoodmachine.com/d/files/65322865879.pdfIn PDF document text
    • https://exihomes.com/userfiles/files/puvuwewaviludup.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161416ba48dea1---jidebagejexojepowof.pdfIn PDF document text
    • http://omni-links-europe.com/images/blog/file/dawodibu.pdfIn PDF document text
    • http://newdimension.su/userfiles/file/55429027102.pdfIn PDF document text
    • http://www.johnrealestate.in/ckeditor-ckfinder-integration/uploads/files/jorinusazaxepa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=mi+9+latest+updatePDF 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_off0000de2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE2D 17332 bytes
SHA-256: 91f6868fd7aaaeef4e331412e18226b565a52c792e8cd3cce50f3e9457394b9e
font_01_sfnt_off00010b1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B1E 10320 bytes
SHA-256: aabce83e545e79cf985980f388b5a8b0b8dd60615a1cd6846e23036beeb0ead3
font_02_sfnt_off00012289.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12289 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1