Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bad5c53081a9705…

MALICIOUS

PDF

81.4 KB Created: 2021-09-17 04:12:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: fc22238c14847dbd4bb324473bcaef7e SHA-1: fe73e42299fb367382a22053c00b6183cfa093a5 SHA-256: 4bad5c53081a970540e837c68bf8e2338e5e4f3b388b93e75b070dd358836d27
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML and ClamAV as malicious, with heuristics indicating it functions as a link farm. Numerous embedded URLs point to potentially malicious or unknown domains, suggesting an attempt to redirect users to phishing or malware sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a strategy to obscure the true destination through multiple redirects and disposable hosting. No scripts were extracted, but the overall structure points to a malicious document delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 http://agro-pasz.pl/ckfinder/userfiles/files/dosujupadutijogenuz.pdf In PDF document text
    • http://wildpflanzen-planung.de/file/sojepebuborinonawitiwawes.pdfIn PDF document text
    • http://www.companyforte.com/imagenes/editor/file/romikazofiximopakelulovix.pdfIn PDF document text
    • http://www.sname.org.tw/sname/ckfinder/userfiles/files/16919070096.pdfIn PDF document text
    • http://talentfuturesservices.com/sharpinstitute/images/files/34837925074.pdfIn PDF document text
    • http://marasintl.com/public/ckfinderuploads/files/vowinurajaw.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/dulolerefon.pdfIn PDF document text
    • https://barrierball.cl/ckfinder/userfiles/files/gebefuvosotuxaxop.pdfIn PDF document text
    • https://arabadvertise.com/userfiles/files/tejado.pdfIn PDF document text
    • http://bijverhoeven.nl/uploads/files/74573144120.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/fagozosunesaxiv.pdfIn PDF document text
    • https://optical-axis.com/uploads/files/202109072202545369.pdfIn PDF document text
    • http://sunnysolutions.it/uploads/assets/file/sewusilezexeg.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/nokafiziv.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/kanopul.pdfIn PDF document text
    • http://grawerlik.pl/userfiles/file/gujiferosukulesiroladi.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/161404d85eea7e---xujibodefibubekefuvubuvel.pdfIn PDF document text
    • https://appvid.eus/userfiles/files/56625723143.pdfIn PDF document text
    • https://durimawar.com/contents/files/93695166923.pdfIn PDF document text
    • http://tnshoppingbag.com/upfiles/file/sadovudegilabif.pdfIn PDF document text
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/tarobazulukujutabifavefuj.pdfIn PDF document text
    • http://harc-ias.vn/Images_upload/files/24620307780.pdfIn PDF document text
    • https://jgranit.pl/userfiles/file/40273780768.pdfIn PDF document text
    • https://cosmopolitanhotel.eu/uploads/wysiwyg/files/daliduwusiwatu.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f6ac06f0fb---90724464783.pdfIn PDF document text
    • http://ahchala.com/img/file/96037689813.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=how+to+get+80+robux+on+pc+2020PDF 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_off0000d85a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD85A 17736 bytes
SHA-256: a74d9fdacffaa41589a878f3d19a53a5f8d5dcab4417508142396f36b7cfc1f2
font_01_sfnt_off00010684.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10684 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E9B 10952 bytes
SHA-256: 38add065702b9f330aa486356f35571624a7fcc2bd6cb16c1cb5e8e35046564d