Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cda64a7989dd05a…

MALICIOUS

PDF

72.0 KB Created: 2021-09-19 04:56:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1d0f3ac919c8b6f472d57eb852283d06 SHA-1: f316c3c9a46ead79f175658b45319e201a685608 SHA-256: 7cda64a7989dd05a06e7d7c8a6fe8ae2e5658371558830f7ab7f29ea46323c3c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to other PDF files hosted on various domains, suggesting a link farm designed to distribute malicious content. The presence of external URI heuristics and link farm detection further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://bulongvungtau.com/media/ftp/file/faxobejorukedodorotoviga.pdf In PDF document text
    • http://nanopena.cz/upload/file/gisizawawa.pdfIn PDF document text
    • https://hogozaty.com/ckfinder/userfiles/files/jivetixute.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613b58c21b5c0---8430675530.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358f1240f9d---23598523628.pdfIn PDF document text
    • https://taiwan-tiaya.com/upload/tiaya_official/files/90258351912.pdfIn PDF document text
    • http://barahi.com/assets/userfiles/files/78313723081.pdfIn PDF document text
    • http://miraesusan.com/ckupload/files/18610420493.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210914135230.pdfIn PDF document text
    • http://costruzionibulagna.it/userfiles/files/lezimonigawoxodasod.pdfIn PDF document text
    • https://groupburuemas1.com/contents/files/37315810986.pdfIn PDF document text
    • http://trunglamdecor.com/uploads/userfiles/file/89536246179.pdfIn PDF document text
    • http://hycxchina.com/filespath/files/20210912142808.pdfIn PDF document text
    • http://4reality.cz/userfiles/files/11685249651.pdfIn PDF document text
    • http://satyamtracparts.com/userfiles/file/70589542369.pdfIn PDF document text
    • http://popmetre.com/news/files/8812158319.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff5b387189---xetogeliwiwisodoma.pdfIn PDF document text
    • http://werkschoenenverkoop.nl/images/docman/files/21593599787.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614680478a9a1---65336411033.pdfIn PDF document text
    • http://3m18.com/images/editor/files/rebigozoz.pdfIn PDF document text
    • https://hinaweb.com/upload/file/263942367.pdfIn PDF document text
    • http://pilot-market.ru/new/files/file/49723578923.pdfIn PDF document text
    • https://cicasoftavukatwebsitesi.demowebsiteleri.com/upload/files/85341814850.pdfIn PDF document text
    • http://logtech.cz/foto/Image/file/80106093542.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=dua+for+someone%27s+good+healthPDF 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_off0000ba9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA9A 15420 bytes
SHA-256: 819eae1eb119916d05dbebd5d5a5ab7f044d60e32402221b6b8226569412f735
font_01_sfnt_off0000e187.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE187 10844 bytes
SHA-256: a6717737a878c7ea20c55d7b501f66b83bb002764330a5966dd99a4816a1f2be
font_02_sfnt_off0000fa3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA3C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1