Malicious PDF — malware analysis report

Static analysis result for SHA-256 a99a953c1d45eefb…

MALICIOUS

PDF

74.1 KB Created: 2021-09-18 21:55:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 679272715ef5fbf0a915d31b98218233 SHA-1: fa6a2031f8438c389786a1800f2d0573090e07a5 SHA-256: a99a953c1d45eefb35e01150f591bab199b6ff8d8b05c84e57ebe8db75c24f0c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristics identified it as a link farm, with numerous embedded URLs pointing to other PDF files, suggesting a distribution or phishing campaign. The presence of external URIs and the overall structure point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://yuanhebiotech.com/upload/files/49304976503.pdf In PDF document text
    • http://joelcsimonesq.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/13171080811.pdfIn PDF document text
    • http://qdsenfeng.com/data/files/24034644071.pdfIn PDF document text
    • http://domki-kopalino.pl/pliki/tegizasefaf.pdfIn PDF document text
    • http://manpukuorder.com/uploads/files/tefevutu.pdfIn PDF document text
    • http://aircond.md/upload_fck/file/xuvavog.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/tuwokiroribotazuxitigixop.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/4924d1708bd2c42342947156645d9b33/bugapib.pdfIn PDF document text
    • http://nprofit.hk/userfiles/fijufekowuwupujo.pdfIn PDF document text
    • https://lexcyberia.com/userfiles/files/jirulajafedupubu.pdfIn PDF document text
    • http://vibrobeton.by/pics/files/bexubemoturiwutegaf.pdfIn PDF document text
    • https://sd-olimp.hr/files/4072870769.pdfIn PDF document text
    • http://yjccnc.com/upload/files/kegidalarezanij.pdfIn PDF document text
    • https://peltonfell.org.uk/ckfinder/userfiles/files/mutadajog.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/161424efd3b277---10688243858.pdfIn PDF document text
    • http://usateatop.com/_upload/files/62563173268.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/57508586725.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/gutofidokewuwa.pdfIn PDF document text
    • https://mehreganimaging.ir/images/upload/files/18058385985.pdfIn PDF document text
    • http://teplo76.ru/uploads/file/vaxixomagitazujipe.pdfIn PDF document text
    • http://madinaboys.com/easydo%20v2.00/files/uploads/vogevajudoboraxipa.pdfIn PDF document text
    • https://jdrum-music.com/uploads/ckfiles/files/66498768734.pdfIn PDF document text
    • http://hoanhaochemical.com/uploads/files/5758163808.pdfIn PDF document text
    • http://sarica.com.tr/ckfinder/userfiles/files/fukalof.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=the+immortals+of+meluha+pdf+free+download+in+tamilPDF 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_off0000bf51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF51 16484 bytes
SHA-256: 7367da89bae4b564f46eae34696e82b04c30a10d9a8cdb14c0ce681101473c48
font_01_sfnt_off0000e96c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE96C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010183.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10183 10912 bytes
SHA-256: a2eb2d4f94d91f778520f587d8a028f1fa68340e220e376d0a1eed41f6d3a7a2