Malicious PDF — malware analysis report

Static analysis result for SHA-256 974fbc4028a04419…

MALICIOUS

PDF

71.9 KB Created: 2021-09-17 21:44:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e90f10a9e5e69225f082f35067dfe2fc SHA-1: 497377d2c10073fe6c676d86204dc2f2870adbdf SHA-256: 974fbc4028a0441963ca1bb7f98b21e4440e6c17e5f64e544c4d4847bb6a3edc
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. The presence of numerous external URIs, many pointing to PDF files on various domains, suggests a link farm or redirection mechanism. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The sample's structure and heuristic firings align with known PDF-based malware delivery methods.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://thuhuonglacquer.com/uploads/news_file/vilibepijividuvuvolami.pdf In PDF document text
    • https://jeneifogaszat.hu/cikkdata/files/sofazetixodititojig.pdfIn PDF document text
    • http://es-manzokudou.com/yamituki-n/uploads/files/fafipukipifepibivutenupe.pdfIn PDF document text
    • http://centronegozi.com/public/zozobutepunamevupovut.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/pimeletazurafomivibaridut.pdfIn PDF document text
    • https://k31szmq42-nu28.com/contents/files/gazifalejelumok.pdfIn PDF document text
    • http://www.alexgis.com/siteuploads/editorimg/file/20576507125.pdfIn PDF document text
    • https://digireg.com/upload/12018304593.pdfIn PDF document text
    • https://globalathena.com/ckfinder/userfiles/files/momagupesogirekopodibudu.pdfIn PDF document text
    • http://erulingua.hu/uploads/content_files/files/xuzotidavitudigumidiso.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/161423982c0f6d---votunewadabakemojanuw.pdfIn PDF document text
    • http://xn----7sbndn5at.xn--p1ai/uploads/files/wopuwi.pdfIn PDF document text
    • http://oppedisanorobertosrl.com/userfiles/files/pitokijavorar.pdfIn PDF document text
    • https://www.nhabe.com.vn/ckfinder/userfiles/files/63708174212.pdfIn PDF document text
    • https://hv2barrier.com/application/third_party/ckfinder/userfiles/files/32315992413.pdfIn PDF document text
    • http://singer-island-condos.com/userfiles/files/24362567060.pdfIn PDF document text
    • http://www.deopendeur.org/imgUser/file/80127277461.pdfIn PDF document text
    • http://crestviewshopping.abwingsmd.com/uploads/files/kibitagetazenuw.pdfIn PDF document text
    • https://www.rongoldmanlaw.com/system/js/back/ckfinder/userfiles/files/jozirazudoxijivere.pdfIn PDF document text
    • http://reversetheclocknow.com/ckfinder/userfiles/files/73491855899.pdfIn PDF document text
    • http://highdeal.linkeo.net/ckfinder/userfiles/files/zipoget.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613ec01080e30---tibezutowolepe.pdfIn PDF document text
    • https://yasacompany.com/upload/files/gekosewivujotebepu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=watch+any+tv+show+free+onlinePDF 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_off0000b80a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB80A 10692 bytes
SHA-256: bcef038a5c0348513e6f55db9d0b1c2d70fd9506a054f1af41265fec8f049202
font_01_sfnt_off0000d0a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0A0 16032 bytes
SHA-256: 378da3ab76e932b0f36223fce17883c1de993da8ee90aefa65cfd6c48c1f00b8
font_02_sfnt_off0000fa06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1