Malicious PDF — malware analysis report

Static analysis result for SHA-256 4313ad6d87afba87…

MALICIOUS

PDF

84.7 KB Created: 2021-09-17 06:02:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c5ee4e0cc69132c34625bfb8193cf138 SHA-1: ffd426611ec3a2b78d2560ab7c04fe7c5ffd744f SHA-256: 4313ad6d87afba871a2bbc58381f0b1d4ad9241ca8f5ac4b027c598df122f13f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, suggesting it functions as a link farm or phishing lure, directing users to potentially harmful external sites. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to exploit users through these links.

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 https://medvor.ru/uplcv?utm_term=developing+android+apps+with+c%23 PDF link annotation
    • http://cegled.varosom.hu/userfiles/files/71200664937.pdfIn PDF document text
    • http://dalieuht.com/app/webroot/uploads/files/solowag.pdfIn PDF document text
    • https://kolegium.inaheart.org/upload/files/lifivadaxegaxabiwepo.pdfIn PDF document text
    • http://studiopol.it/userfiles/files/2815465523.pdfIn PDF document text
    • http://iseveranscopy.com/upload/editor/file/29742267047.pdfIn PDF document text
    • http://packagingandfoodmachinary.com/userfiles/file/lojedodugozaniteriwopa.pdfIn PDF document text
    • http://poetische-malerei.de/web/editor/files/vufowopi.pdfIn PDF document text
    • https://granitabrasive.hu/editor_up/visobusadodivolukusika.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/34747199265.pdfIn PDF document text
    • https://cytokin.ca/upload/editor/file/zogafozirefupigasewamuwa.pdfIn PDF document text
    • https://almentispharma.com/ckfinder/userfiles/files/54316809299.pdfIn PDF document text
    • https://franchisefarm.franchiseharbor.com/files/files/11504260457.pdfIn PDF document text
    • https://maria-galland.ru/files/file/ripozela.pdfIn PDF document text
    • http://cuakeobinhduong.com/upload/files/79114416650.pdfIn PDF document text
    • http://eternaseguros.net/files/files/fojigiroziv.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/rosonasasebiganosesamo.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1612f4c681fa65---96075896173.pdfIn PDF document text
    • https://etcbt.com/userfiles/file/46018610241.pdfIn PDF document text
    • http://cyc.cz/pictures/clanky/files/kemamibela.pdfIn PDF document text
    • https://stallion-international.com/userfiles/file/besiwiredujenorivoroxaje.pdfIn PDF document text
    • http://italiangreyhound.pl/img1/userfiles/file/35978105146.pdfIn PDF document text
    • https://ezgoe.com/10005001208290177/ckfinder/userfiles/files/tejegagizupi.pdfIn PDF document text
    • http://domusanna.it/userfiles/files/pigitere.pdfIn PDF document text
    • https://binarbaidequipment.com/public_html/userfiles/file/nibezizojarurubola.pdfIn PDF document text
    • https://tvmreza.tv/ckfinder/userfiles/files/10482272285.pdfIn PDF document text
    • 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_off0000e600.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE600 10944 bytes
SHA-256: e4344f7b51bd173a6e63ccb2b2a9882e47a4c7e8a01eff8263d1d128ceb4a921
font_01_sfnt_off0000ff30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF30 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011742.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11742 17848 bytes
SHA-256: 5b56c1aeb71f043e7b7f9435e510ee1401a5d91fd854bcca6d50fb85b5c0db0c