Malicious PDF — malware analysis report

Static analysis result for SHA-256 f636b7a5beb194cd…

MALICIOUS

PDF

84.5 KB Created: 2021-10-21 08:49:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6483250f3da9edcc3e7bf0e6172fddd2 SHA-1: 07050f96aaf8fe72d7616a7cfac6e5241a9dd640 SHA-256: f636b7a5beb194cd624877735d8fbab0768e85681b638bd7f99848c94d19a376
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating embedded JavaScript and a link farm structure. The presence of embedded JavaScript suggests an attempt to execute malicious code, likely to download additional payloads or redirect the user to phishing sites. The numerous external links, many pointing to PDF files on disposable hosting, further support a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://vejwun.cz/images/22124800947.pdf In PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/pakewiriloxevasebure.pdfIn PDF document text
    • https://aspirecambodia-edu.org/userfiles/file/43816438513.pdfIn PDF document text
    • https://blnk.eu/userfiles/files/97250638934.pdfIn PDF document text
    • https://kemxoithanhhang.vn/app/webroot/files/images/pages/files/kazasileru.pdfIn PDF document text
    • https://samoinstitute.samoinstitute.mn/uploads/assets/file/25841560272.pdfIn PDF document text
    • http://wsospice.org/uploads/userfiles/file/file/jovawedoxeruwipas.pdfIn PDF document text
    • http://gold-carsales.com/js/upload/files/fowosunofoxemumenoluju.pdfIn PDF document text
    • http://inlovehuahin.com/file_media/file_image/file/wezowujebofewuv.pdfIn PDF document text
    • https://cogi.sed-hut.pl///files//editor/file/37669866791.pdfIn PDF document text
    • http://tageedesign.com/ssmpt/documents/file/takuzolosafigim.pdfIn PDF document text
    • http://ksiclub.org/projects/achievemore/admin/upload/fckImages/file/10805064092.pdfIn PDF document text
    • http://ciba.lv/uploaded/file/99383057433.pdfIn PDF document text
    • http://amicalelaique-guyancourt.fr/ckfinder/userfiles/files/mirazolozikariz.pdfIn PDF document text
    • http://fotografoenricogiampieri.it/userfiles/files/mibajexogos.pdfIn PDF document text
    • http://www.jucadent.es/ckfinder/userfiles/files/13954251683.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/39jul07rj43klkr9aqd6ipjjpa/27046153288.pdfIn PDF document text
    • https://nstyapi.com/resimler/files/gakitagatovuwenutebak.pdfIn PDF document text
    • https://angkaindaman.com/contents/files/ferofogitinuveni.pdfIn PDF document text
    • https://currenwatch.myhost360.cn/file/upload/files/10-06-06-59-21-20.pdfIn PDF document text
    • http://altinay-law.com/images/file/64865405765.pdfIn PDF document text
    • https://www.idd.no/ckfinder/userfiles/files/bakalegetivuwugamopobijub.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/98754055048.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/2I9n2o-U8HI/uplcv?utm_term=it+is+appointed+unto+man+once+to+die+nkjvPDF 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_off0000e65b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE65B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE72 10868 bytes
SHA-256: 68c7aa63cdb94d8586a9a1f77948277c7c71fb14e6da9ac7ec44cabb7c68796c
font_02_sfnt_off0001178c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1178C 17328 bytes
SHA-256: 8de56269a94dc5a1efdece576b5a758db2578d18540ff3b32fde8bcfc15c188f