Malicious PDF — malware analysis report

Static analysis result for SHA-256 39fa563b9fea954c…

MALICIOUS

PDF

79.9 KB Created: 2021-09-17 19:58:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4ffc0410bdad4c4c9c5ef84c70dd7c06 SHA-1: 43dfe610172f7b094a57015570f1af9a3a208045 SHA-256: 39fa563b9fea954c4becea36eebdf7633fdbe2734e7e311927fdca2e96d50c5f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution lure. The presence of numerous unknown URLs further supports this, as they likely host malicious payloads or redirect to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://runhouchem.com/upload/files/nesuvofoli.pdf In PDF document text
    • http://thegioichuyendong.info/app/webroot/upload/files/puvokimodenexofugusenobo.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/2721990866.pdfIn PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/2cc47f1a203ef356883dc18e89b204a3/dogedixegom.pdfIn PDF document text
    • https://tutorbolivia.com/userfiles/file/nunononivikukad.pdfIn PDF document text
    • http://talleresjpg.es/img/file/topulisojuparidowifid.pdfIn PDF document text
    • https://hantverksakuten.se/ckfinder/userfiles/files/61702013918.pdfIn PDF document text
    • http://yuli-china.ru/d/files/sawojaxiwupiwupixafumi.pdfIn PDF document text
    • http://kemnhapkhau.com/upload/files/mokovuxixomedaxolux.pdfIn PDF document text
    • http://xindeshiye.com/uploadfile/file///2021091715265097.pdfIn PDF document text
    • https://hsse.hssanesteban.cl/files/lalegizudifugafureda.pdfIn PDF document text
    • http://okna-kurska.ru/page_edit/_samples/userfiles/files/volirarumetep.pdfIn PDF document text
    • http://24hnbc.com/assets/ckfinder/core/connector/php/uploads/files/galujiropered.pdfIn PDF document text
    • http://clarklawtexas.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/38223496050.pdfIn PDF document text
    • http://gezond-trakteren.nl/kasteel-doornenburg-img/bestandenfile/wagevodosemunage.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/rd5h7l7h5d93ll0t1u5fep2e1g/67820962005.pdfIn PDF document text
    • http://vnationwide.com/userfiles/files/motizobijegajorixetuz.pdfIn PDF document text
    • https://edarky.net/data/file/juzikobo.pdfIn PDF document text
    • https://thuanxuongmonmb.com/admin/webroot/upload/image/files/napemis.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/161300a5c0333c---86948798751.pdfIn PDF document text
    • http://thietbikhachsanvinhhung1.com/upload/files/jepifuvanuxunewevalejogiw.pdfIn PDF document text
    • https://paymentor.nl/uploads/file/41587944891.pdfIn PDF document text
    • https://taxfirma.com/userfiles/file/25737127849.pdfIn PDF document text
    • http://around-sicily.net/userfiles/file/5951967535.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=chhota+bheem+game+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_off0000d156.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD156 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e968.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE968 18736 bytes
SHA-256: ff025ea432636c1abd70d6fa2327e12817966c66232d7cf3c3640efa924dc145
font_02_sfnt_off00011abd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ABD 10452 bytes
SHA-256: b4258b4ec30a61d8f2879d7e97c371f11f22c69ecf391ec56bad08328bc94fd1