Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b1339699561f7a1…

MALICIOUS

PDF

70.7 KB Created: 2021-06-05 01:25:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: edb7b27578046c268df40ea5c4cf598b SHA-1: 2159bbad3678baff62acd70083d679d331bd4e6f SHA-256: 4b1339699561f7a1778ae483f652cc451de04c8eeca20faa02c671839be4aed3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm or redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as phishing. The document body, though heavily obfuscated, contains a title related to 'storyboards' which is likely a lure to disguise the malicious nature of the links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://crysiq.ru/uplcv?utm_term=how+to+make+and+use+storyboards PDF link annotation
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080035c851dc---jafakexonunefaxilinunag.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/c53d55d962ae6c66f22a166a7e4018da/givatukapebovodisuxel.pdfIn PDF document text
    • http://mazdooradda.com/userfiles/file/patutavivot.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160925cf3eb039---53986331508.pdfIn PDF document text
    • http://ash-graphy.com/userfiles/file/7937150197.pdfIn PDF document text
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/ec5788ac0cbb858039237f71c4fb0849/12857025472.pdfIn PDF document text
    • http://ipmarketing.net/userfiles/file/ziwuzilizufegevalatif.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/5toervb57e921rmisugn7r3pr1/77254361899.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/11c9832271a4fe022c4875fad75654cd/52769768412.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/f4e1c53a3d534e7dbf2b378a7f251a1b/62683851832.pdfIn PDF document text
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/1da30ea29ff988741b29aee41033713a/30534203434.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa3ff76574a---mufufezagabetenowebe.pdfIn PDF document text
    • http://kolesnikov.pro/ckfinder/userfiles/files/48605630971.pdfIn PDF document text
    • https://www.varisistanbul.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606da6749bb12---jotokakeforezubiximuwimo.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/8hji3voi3teirdd35tgfgtj8t8/dazoda.pdfIn PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/c1cbb4c7fe5f618e382da683f7896eda/suvisuwigoba.pdfIn PDF document text
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abe02f7b979---37986823440.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d907.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD907 5296 bytes
SHA-256: c245188fab8139f236f8702026172a41a779b6f23da038120fb0cb4c9ca30eaf
font_01_sfnt_off0000eb01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB01 10152 bytes
SHA-256: 378961106bc04d2226ee67128189e298e09ab0317c9a5f247648c07c8d6d6c4f