Malicious PDF — malware analysis report

Static analysis result for SHA-256 1055f4c9d147a142…

MALICIOUS

PDF

70.8 KB Created: 2021-09-08 16:55:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9cbf4a2f69fed17ff798666605c26edc SHA-1: c659cdec41de34382d6b788dfdc612b925cc906f SHA-256: 1055f4c9d147a142780a93e07b10e5a977220fddc2deace0805742cb456eb4ed
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which are hosted on suspicious domains and appear to be part of a link farm, suggesting a phishing or malware distribution scheme. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating the PDF is designed to direct users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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.
  • 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://xn--989ap7r0xbd5x.com/upload/fckeditor/file/54576718331.pdf In PDF document text
    • http://architettotoma.it/userfiles/files/zedojusuxifuv.pdfIn PDF document text
    • https://denimder.org/resimler/files/35375055009.pdfIn PDF document text
    • http://artpolinakuzina.ru/pict/file/jonitifanotafixosunoduwig.pdfIn PDF document text
    • http://2017.letnifestiwal.pl/ckfinder/userfiles/files/50246788822.pdfIn PDF document text
    • http://ohadalegistrocbarter.com/ckeditor/uploads/files/bitazu.pdfIn PDF document text
    • https://thaibamboorestaurant.ca/phpsites/bard_ford/uploads/file/41988904168.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/23445355030.pdfIn PDF document text
    • http://taikenplan.jp/ckfinder/userfiles/files/mijiwewadegubu.pdfIn PDF document text
    • http://nordicwalkingturak.hu/_user/file/204037947.pdfIn PDF document text
    • http://librojuridico.com/aym_images/files/13847735843.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/87073326934.pdfIn PDF document text
    • http://dfanchem.com/upload/files/nemuretobuvofubadogiwerex.pdfIn PDF document text
    • https://holycrosshealthcare.com/userfiles/files/94905454937.pdfIn PDF document text
    • http://local-minicab.com/survey/userfiles/files/1446540245.pdfIn PDF document text
    • https://www.piramideidiomas.com/ckfinder/userfiles/files/70559513808.pdfIn PDF document text
    • http://rileyillustration.com/images/agency/files/92472901812.pdfIn PDF document text
    • http://deeringbayrealestate.com/userfiles/files/40583588504.pdfIn PDF document text
    • http://pttaccounting.com/userfiles/files/tadapibonudejefugebal.pdfIn PDF document text
    • http://problemconsulting.com/img/download/files/2991448843.pdfIn PDF document text
    • http://melly-incendie.fr/img_db/fusedovexipunopi.pdfIn PDF document text
    • http://xn----dtbhwhggdaoqfh3d.xn--p1ai/media/file/55529270143.pdfIn PDF document text
    • https://turkihale.com/userfiles/file/In PDF document text
    • https://chongtham68.com/app/webroot/uploads/files/61380510169.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=defining+relative+clauses+exercises+pdf+4+esoPDF 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_off0000b288.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB288 11140 bytes
SHA-256: 9122ad34df93f99dd31193f9a64d4dfbb3bfacbda39de7dc60b37c249b4c61a4
font_01_sfnt_off0000cc94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC94 16024 bytes
SHA-256: d2cb819adb07e2edb3471ee9d0396654fab064da248157321e0c0c133b54b16d
font_02_sfnt_off0000f552.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF552 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1