Malicious PDF — malware analysis report

Static analysis result for SHA-256 43d421730adc65d7…

MALICIOUS

PDF

69.1 KB Created: 2021-09-14 03:07:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 54a568c2b49c26e8ae566a7ad07b6382 SHA-1: fda794942e13d7619d7fb2fa7f79d26f29a2092a SHA-256: 43d421730adc65d7158fffa45ccabd8d896b1502ca14704417a5065656739e8d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs and is identified as a link farm hosted on disposable domains, suggesting a phishing or malware distribution lure. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards techniques used for initial access and potentially client-side execution.

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://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/161313e6738719---jemufawubamaja.pdf In PDF document text
    • https://digireg.ru/upload/6036486172.pdfIn PDF document text
    • http://e-restauracion.com/app/webroot/files/uploads/files/11652266529.pdfIn PDF document text
    • http://ngnjl.com/userfiles/files/69463581850.pdfIn PDF document text
    • http://tverzhilservis.ru/foktver.ru/ckfinder/userfiles/files/66261870426.pdfIn PDF document text
    • http://xn--zb0by3yusal20ak5lcidnwigi.com/ckfinder/userfiles/files/1631387896.pdfIn PDF document text
    • http://casier-a-bouteilles.fr/file/somujusixodozefowiwi.pdfIn PDF document text
    • https://www.aifimm.it/admin/inc/ckfinder/userfiles/files/97407291996.pdfIn PDF document text
    • https://gizaviation.com/uploads/files/84706729178.pdfIn PDF document text
    • http://bapassamarinda.id/assets/ckfinder/core/connector/php/uploads/files/tufolebiforijezijuzezo.pdfIn PDF document text
    • http://perfekt-dom.pl/designhome/admin/userfiles/file/mobeganexapokoxitujenos.pdfIn PDF document text
    • https://takarasushimn.com/userfiles/files/maxidapumejidozo.pdfIn PDF document text
    • https://likeevent.it/writable/public/userfiles/file/47705989266.pdfIn PDF document text
    • https://emilline.dk/ckfinder/userfiles/files/nijirolovavavidotaxedugaf.pdfIn PDF document text
    • https://support-trevianum.nl/userfiles/files/resabejilomusedetor.pdfIn PDF document text
    • http://coverybox.box8websites.com/ckfinder/userfiles/files/12694574410.pdfIn PDF document text
    • http://wohingltd.com/userfiles/goruxeworitizi.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/risozepox.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/37479917773.pdfIn PDF document text
    • http://ned.ru/uploads/files/tuwoberozesewutexej.pdfIn PDF document text
    • http://duet-czluchow.pl/userfiles/file/17768202209.pdfIn PDF document text
    • https://jazykovytabor.topenglish.sk/app/webroot/gallery/files/68653247137.pdfIn PDF document text
    • https://profesa.net/userFilesfile/57262247588.pdfIn PDF document text
    • http://owop.challengersports.com/ckfinder/userfiles/files/vitiliparo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=local+news+channels+on+firestickPDF 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_off0000b0fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0FB 15068 bytes
SHA-256: e9c63c68355fff4acd9c0ff8687ab9573d5ec639b1728c269f92c288137ac950
font_01_sfnt_off0000d6e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eeff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEFF 10568 bytes
SHA-256: 6696f2f9aeb24a5634eb5c64b75e5f76103a506e7324576fa8059b50a9d862aa