Malicious PDF — malware analysis report

Static analysis result for SHA-256 db0c45dcba1f8af9…

MALICIOUS

PDF

82.3 KB Created: 2021-09-11 15:53:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: fbc9fc8577c5dd3afbcb079b4fc789f0 SHA-1: 8aac515aeca3613fc15720d12a6143c5a4b6d49b SHA-256: db0c45dcba1f8af9c1aaf9507c8f8031be894f36375bc8256c3b88d3c8ca3b5c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a phishing or trojan threat. The presence of numerous embedded links, many pointing to external PDF files, and a heuristic indicating a 'disposable link farm' suggests an attempt to distribute malware or phish for information. The 'SE_DOWNLOAD_BUTTON' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://styropapex.pl/userfiles/file/37439699615.pdf In PDF document text
    • https://zlataraburmevuckovic.com/files/gazupofurapokanudopunaz.pdfIn PDF document text
    • http://erpsamik.com/ckfinder/userfiles/files/34483258982.pdfIn PDF document text
    • https://sanipro.ma/app/webroot/uploaderfiles/luzorubejivufexa.pdfIn PDF document text
    • http://k-sta.kr/FileData/ckfinder/files/20210911_1661C8133BDA21D6.pdfIn PDF document text
    • https://transilvaniafishing.ro/app/webroot/files/userfiles/files/nojemisisowugutuz.pdfIn PDF document text
    • http://www.boldino-hotel.com/ckfinder/userfiles/files/39485181021.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///sujefupagusukam.pdfIn PDF document text
    • http://parbatsamajjapan.com/img/files/files/47322041182.pdfIn PDF document text
    • https://hbphoto.ca/resimler/files/8682268947.pdfIn PDF document text
    • http://shahgrp.com/uploads/3252896607.pdfIn PDF document text
    • http://hasdeu.md/data/userfiles/files/reduwidowepudibolilojama.pdfIn PDF document text
    • http://bifruit.mk/ckfinder/userfiles/files/bulevad.pdfIn PDF document text
    • https://namdolove.com/FileData/ckfinder/files/20210901_123AF2C679147857.pdfIn PDF document text
    • http://ichieh.tw/uploads/files/202109022121026832.pdfIn PDF document text
    • http://pro-roubenky.cz/UserFiles/File/rulepituxumeg.pdfIn PDF document text
    • https://www.koreayokogawa.com/ckfinder/userfiles/files/wivetufudesakizexubawil.pdfIn PDF document text
    • http://daiichihousing.net/uploads/news_file/87123840978.pdfIn PDF document text
    • https://yellowstonewildlife.com/1943833357.pdfIn PDF document text
    • http://studiorapizza.it/userfiles/files/29103275259.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///gefavarimit.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0f5295125---1053891387.pdfIn PDF document text
    • http://dorisemitchell.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jumefujakutar.pdfIn PDF document text
    • http://sinoscaform.com/upload/ckimg/files/202109080909383901.pdfIn PDF document text
    • https://gornjastubica.hr/files/wodovazezoroditegeren.pdfIn PDF document text
    • http://evrofurnitura.by/elax-furnitura.ru/uploads/files/96814639907.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=super+vpn+pro+mod+apk+downloadPDF 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_off0000dbfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBFE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f415.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF415 10616 bytes
SHA-256: 3ca688b6718061a6c6fe9fef7a42c1671b6b4dd1b972bbcc57f13f33d9a5e745
font_02_sfnt_off00010c5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C5B 18404 bytes
SHA-256: eafed2901697488a416a13b086d98ee1d6fc698199bf58937bd0442eb7d56499