Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5fa2466004951f2…

MALICIOUS

PDF

70.7 KB Created: 2021-09-19 17:53:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b662a9adb05d3876ebeeca3267e9e564 SHA-1: 2638e8c398305b36d9575ed8bf7efc28d57bf6bc SHA-256: c5fa2466004951f29fcd66fd0938d091e65f9ba9040aae6ac20d5958bfebbbbb
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. Heuristics indicate it functions as a link farm, pointing to multiple compromised or disposable hosting sites. The embedded URLs suggest an attempt to direct users to external, potentially malicious content, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://hatowo.com/app/webroot/uploads/files/52643248478.pdf
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/49416799408.pdf
    • http://viettelhaiphong.me/data/dulieu/files/75652497591.pdf
    • http://qualityfirstservices.pro/testingsites/advantage_aviation/assets/media/file/rosololivuxiweso.pdf
    • http://khachsansapa.vn/webroot/img/files/tuvebenosajivujedoz.pdf
    • http://mikailang.com/userfiles/file/20210916181104_960290954.pdf
    • https://windfreeklima.com/upload/ckfinder/files/47266503507.pdf
    • https://funbugs.ie/files/file/69199194447.pdf
    • https://thefertilizergranulator.com/d/files/85404772852.pdf
    • http://glamour-nsk.ru/ckfinder/userfiles/files/sumafupijefukezigeruf.pdf
    • https://cytokin.ca/upload/editor/file/92584062378.pdf
    • http://benly-carson.com/product/files/foludixiduxokopogumes.pdf
    • https://kueapem.com/contents/files/webelaxesis.pdf
    • http://abwcockeysville.com/uploads/files/tojizeruwag.pdf
    • http://lyshiying.com/d/files/bumesu.pdf
    • https://bushregenerators.com/userfiles/files/54418171276.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614525b4d5168---3743356335.pdf
    • http://kipia-nn.ru/userfiles/file/modijizizo.pdf
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/64d9d6fb582863d9bdea07eb6cb3f099/kujolofatakapuzoworuduz.pdf
    • http://jshanwoo.com/ckfinder/userfiles/files/gomodatoz.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613674797322a---rabupevuj.pdf
    • https://x-leather.com/radsportfiles/file/gimokakobakifakerifop.pdf
    • http://favourtec.com/attachment/file/lagigonimub.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ccf9332016---94550906835.pdf
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144247b31eb2---45042830646.pdf
    • http://immobilier-valence-agen.com/userfiles/file/87271797682.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=android+replace+dialer
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b6d8.bin
e83485cb17cdea6b4601e241d3b413c54c0f8c3a537fee7faaf98e1e371df3c0
pdf-font-stream PDF embedded font (sfnt) at offset 0xB6D8 10220 bytes
font_01_sfnt_off0000cdc8.bin
09ee0ae796b0e6ce2401d7df9f226d431791ed875ec5c42e7883f9ac47cee6c7
pdf-font-stream PDF embedded font (sfnt) at offset 0xCDC8 15544 bytes
font_02_sfnt_off0000f57c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF57C 16792 bytes