Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4716ba48bb7c25f…

MALICIOUS

PDF

74.5 KB Created: 2021-10-08 04:32:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4dc363e12921dfd23ba1875977d05533 SHA-1: cf36e84a0b8c53ec01e743ed680d9a4bcf6ebaf4 SHA-256: d4716ba48bb7c25ff65d4fc9b78a6f322fa26305ba94064b78228b168d38d543
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to suspicious domains and are structured as a link farm, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://thebrownbag.vn/upload/files/legaw.pdf In PDF document text
    • http://webinaris.eu/ckfinder/userfiles/publics/files/xewetukidasudipotusali.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20211002182109.pdfIn PDF document text
    • http://www.skk.com.hk/admin/ckfinder/userfiles/files/zozusoreliko.pdfIn PDF document text
    • https://rajakeempat.com/contents/files/nobikejimevidefuxifufo.pdfIn PDF document text
    • https://exhibitproplus.epponline.com/mentorfinancial/page_images/file/wokoro.pdfIn PDF document text
    • https://doanhnghiepvietnam.org/img_duhoc/files/95104255499.pdfIn PDF document text
    • http://copy2d.com/ftp/image/file/nobuworerexoninasubebaje.pdfIn PDF document text
    • http://pileki.com/imgup/file/71949923696.pdfIn PDF document text
    • http://aytekinpolatel.com/image/files/fubijitizojatuxurikamede.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/megepabedopexiluxezolaki.pdfIn PDF document text
    • http://toeicspeaking.net/_UploadFile/Images/file/zurivubirikivaxojolisesi.pdfIn PDF document text
    • https://www.highlandernepal.com/assets/ckfinder/userfiles/files/15404212917.pdfIn PDF document text
    • http://avandcie-automation.fr/ckfinder/userfiles/files/dogojukumaravuzoj.pdfIn PDF document text
    • http://www.tecnobor.com/ckfinder/userfiles/files/nulimuwozupamuvedoxen.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1615f62b9d1237---zolugagevorovojixavor.pdfIn PDF document text
    • http://balony.dmuchance.eu/userfiles/file/6644360942.pdfIn PDF document text
    • http://aadcnfgl.netsociality.com/upload/files/fosor.pdfIn PDF document text
    • http://mintaialuminum.com/d/files/77810132499.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/lejasusubelifigatu.pdfIn PDF document text
    • https://studiecarriere.it/uploads/file/21572277943.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/pasakebikukajuxuba.pdfIn PDF document text
    • http://aylincinarli.com/fckfiles/file/67758189183.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=what+is+hdpe+2+plasticPDF 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_off0000c02b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC02B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d83d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD83D 17492 bytes
SHA-256: 57b0be0c4934b4ec1be0a72ea31da0686c0f61a13b1399aa4a554d14ee2a61f2
font_02_sfnt_off00010490.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10490 10400 bytes
SHA-256: b8c5c065bbb3d37aaad1bb25925246b9f55df301f9ca9ccf84747dff18625cac