Malicious PDF — malware analysis report

Static analysis result for SHA-256 3920ba57b9290978…

MALICIOUS

PDF

78.4 KB Created: 2021-09-16 14:57:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 533b9fc0b5f6fb860da1fccd58345c88 SHA-1: c818ed2bc49bc1d97e1e29e7a3e889b06cc4a757 SHA-256: 3920ba57b9290978861d7dd31c8a7bf3e588fba338e30259c5e8d04ca89e657d
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm and a lure for browser extension installation. The embedded URLs likely lead to further malicious content or downloads, aiming to trick the user into executing code. No scripts were extracted, but the overall pattern suggests a phishing or malware delivery attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://laborke.ru/uplcv?utm_term=android+app+store+png PDF link annotation
    • https://www.vasutaszeneiskola.hu/ckfinder/userfiles/files/78282903741.pdfIn PDF document text
    • https://implantsdentairesdesmoulins.com/upload/editor/file/bebami.pdfIn PDF document text
    • https://rpdev.org/ckfinder/userfiles/files/sawililofegonakuzotifinox.pdfIn PDF document text
    • http://pho32shabu.com/uploads/files/tilusakifopakulufilibixeb.pdfIn PDF document text
    • http://hyswimpool.com/userfiles/41626084212.pdfIn PDF document text
    • http://ciaomamma.hu/editor_up/49698518799.pdfIn PDF document text
    • https://chung-pei.com/userfiles/file/16478135265.pdfIn PDF document text
    • http://hongsung114.com/files/fckeditor/file/gefofemutepujutoma.pdfIn PDF document text
    • http://halongbaycruises.org/upload/files/rujigamanuge.pdfIn PDF document text
    • https://mcdelandes.ca/uploads/file/samakisogapixeva.pdfIn PDF document text
    • http://parcroyale.hk/userfiles/fizulatigaredejos.pdfIn PDF document text
    • http://avvocato-callegaro.it/public/file/66214256678.pdfIn PDF document text
    • http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/7243848945.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210902043652271.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/16141443543b9e---pamapijuvalozuwamib.pdfIn PDF document text
    • http://kingalbertltd.com/uploadedfiles/file/6697815547.pdfIn PDF document text
    • https://mokshadhamnepal.org/userfiles/files/zujivovurilo.pdfIn PDF document text
    • http://elfuklid.cz/foto/Image/file/84167470052.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/0c25d69a46d90f5fc499caf35942352b/zajoxizozudiritupu.pdfIn PDF document text
    • http://turksebruiloften.nl/userfiles/file/60186208151.pdfIn PDF document text
    • http://studiodrago.eu/userfiles/files/tegalexogikepujixedometul.pdfIn PDF document text
    • http://lukasikgroup.pl/Image/files/wuzavalobatoxamifuwido.pdfIn PDF document text
    • https://rachelrom.com/rescontent/file/12429175616.pdfIn PDF document text
    • https://all-stage-meditation.tw/uploads/files/613b33bbc072b.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_off0000cc72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC72 18320 bytes
SHA-256: b805798e02de8d62cb13a7e57bb65a6a08d731da3f2122fae2135517d5c9bd52
font_01_sfnt_off0000fbeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011402.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11402 10504 bytes
SHA-256: 45cfc40d093ff254d015f7c3af6b007cad73fce2161275f7192d7ebb1c637200