Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d48b1cdead9314d…

MALICIOUS

PDF

81.5 KB Created: 2021-09-11 12:32:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 73632c71538a534a694a49cb89bf4260 SHA-1: 8e2e919585e7681fc959e6da2777d58cfcbaa773 SHA-256: 4d48b1cdead9314d2c2d4ec42b605301bbe6a850d3bd658c6982361642681ce5
134 Risk Score

Malware Insights

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

The sample was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous external links, many pointing to potentially disposable domains, suggesting a link farm or phishing lure. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a strategy to obscure the true destination or distribute malicious content across multiple sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://kaus21.com/userData/board/file/99977031535.pdf In PDF document text
    • https://nurea.se/currency/userfiles/file/1154507730.pdfIn PDF document text
    • http://autofox.lt/ckfinder/userfiles/files/47174303555.pdfIn PDF document text
    • http://hferrynetworks.com/FileData/ckfinder/files/20210901_FD6DC9BF57DC29B8.pdfIn PDF document text
    • https://sakura-bashi.com/uploads/files/202109090403571442.pdfIn PDF document text
    • https://norservis.com/files/files/dokawigenujusotugi.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021090516465958.pdfIn PDF document text
    • https://kompaspt2.com/contents/files/gijagebamudovebunuwog.pdfIn PDF document text
    • http://onlinecommerce.bg/uploads/pages/files/16315272611.pdfIn PDF document text
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/nurezejuxozakebalububa.pdfIn PDF document text
    • https://nieruchomoscikomercyjne.co/files/file/64463264715.pdfIn PDF document text
    • http://studiogalata.it/userfiles/files/55830205186.pdfIn PDF document text
    • https://minipowerpack.net/upload/files/robipuwotozudosege.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/xafuxewoxalugakemutel.pdfIn PDF document text
    • https://adikkeempat.com/contents/files/fomakumigerewefiguxuwajoz.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210911080817.pdfIn PDF document text
    • http://ydyb.com/filespath/files/20210909032411.pdfIn PDF document text
    • http://geojeoceanhotel.com/userfiles/file/20210908181707.pdfIn PDF document text
    • https://dehaventransportation.com/home/de/public_html/ckfinder/userfiles/files/97134160655.pdfIn PDF document text
    • http://cachnhietwin.com/luutru/files/49681259659.pdfIn PDF document text
    • https://shoppingplanet.ro/ckfinder/userfiles/files/50140477.pdfIn PDF document text
    • http://splhardware.com/UploadFile/file/2021090704541573499.pdfIn PDF document text
    • http://ldksolar-officialliquidation.com/userfiles/files/puvebiv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=stick+cricket+2+mod+apkPDF 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_off0000d7db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFED 17972 bytes
SHA-256: ad8f9939a3538d59f437b56f83120cffc74728e353417f95a409f85ed92cf9cb
font_02_sfnt_off00011e97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E97 10644 bytes
SHA-256: 73f84bdb4a92023b9f18d0448f46ecb7e3a67d6d4855f6cf1f28487ad5178607