Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec22881a49c947fe…

MALICIOUS

PDF

72.0 KB Created: 2021-09-25 03:31:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b3b3a95ce1de1b10f1664156c5cf01e1 SHA-1: fc089ac9926ba443f2482129ef4ee91f773c4435 SHA-256: ec22881a49c947fe96ca5b8778a0062ac22e3a2b01533b88953a756a9b514815
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or redirecting users to malicious sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a large number of links pointing to disposable domains, suggesting an attempt to obscure the true malicious destination. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://work4shop.cz/userfiles/file/2608169577.pdf In PDF document text
    • https://stonebuild.bg/f/uploads/files/susixogomonotiputolakaja.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/66421088388.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/kf5ooqc46v41fo2km50vr3flne/konexigumoduvaleta.pdfIn PDF document text
    • https://oazapiekna.com/zdjecia/fck/file/74143291942.pdfIn PDF document text
    • http://inruho.ru/ckfinder/userfiles/files/bedipidajiwukimokatem.pdfIn PDF document text
    • http://cmrivestimenti.com/userfiles/files/fuvuvefarinemixijilolovuz.pdfIn PDF document text
    • http://hoaiduc.edu.vn/ckfinder/userfiles/files/bativiweno.pdfIn PDF document text
    • http://daisin1977.com/js/upload/files/55659133594.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/36036231726.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1614bc47f9bf0a---15986053838.pdfIn PDF document text
    • http://andersonlawdecorah.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/majukiluwego.pdfIn PDF document text
    • http://topbondtape.com/uploadss/file/90414359139.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/31632559153.pdfIn PDF document text
    • https://nhabe.com.vn/ckfinder/userfiles/files/gupojop.pdfIn PDF document text
    • http://favourtec.com/attachment/file/vipejuboso.pdfIn PDF document text
    • https://sandipkumardutta.com/ckfinder/userfiles/files/puxojufivovaxoji.pdfIn PDF document text
    • http://lhdrum.com/User_File/UpFile/file/20210913194548_ODIyMjE0NDE4OA==.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/zuladen.pdfIn PDF document text
    • http://nhasachthunam.com/upload/files/3693514839.pdfIn PDF document text
    • http://parkergeneralcontractors.net/userfiles/file/30571853694.pdfIn PDF document text
    • https://emotionalgift.com/ckfinder/userfiles/files/4760521918.pdfIn PDF document text
    • https://expomediainc.com/upload/file/75355473665.pdfIn PDF document text
    • http://nhactheducthammy.com/upload/files/gigodebagumagamarelufepo.pdfIn PDF document text
    • http://boletos.luzservicos.com/ckfinder/userfiles/files/nuzidutesobababux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+call+net+web+api+from+android+appPDF 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_off0000b356.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB356 17728 bytes
SHA-256: 25ed02b655f97d62262d4b577a3196ad5a4d938739219291a62b79e2e87d1213
font_01_sfnt_off0000e12e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE12E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f945.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF945 10832 bytes
SHA-256: 6567e41809342e90c4bd35656e19e3c6cd0f21df2bee78f526ec7b912042d815