Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef525d53420866b3…

MALICIOUS

PDF

72.6 KB Created: 2021-06-19 08:07:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 7f0f17c627d4364b1f76acf528393786 SHA-1: e08e49c051ccc78e8f4b3110e93ee37a328eae0f SHA-256: ef525d53420866b3acb572b291d1b2f3968e12e6c3e383544dad12c4ce9de5d4
156 Risk Score

Malware Insights

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

This PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains a link farm pointing to numerous compromised websites, likely intended to host malicious content or facilitate phishing. Although no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it is designed to redirect users to these external URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • 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://sevimticaret.net/userfiles/file/50397875818.pdf In PDF document text
    • http://www.asslar.de/downloads/nitunitevodunarubomano.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf219852b39---81915528872.pdfIn PDF document text
    • http://getem.plfiles/file/jinage.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fd99755888---40289644900.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/danojafediforudu.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/bf53b77c28d0f312c4e9365660a260cd/270040573.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/2093ac236ad92c3a5dd7d6675276af52/rixamizuka.pdfIn PDF document text
    • http://polyalpan.hu/_user/file/49531200478.pdfIn PDF document text
    • http://24cvety.ru/upload/files/mizivaxewajekuvewekamik.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607807f93dab0---zovezeneziruwisukuvuwaduv.pdfIn PDF document text
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/16083f39474f4b---ponolekumono.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/5tmn0nhokk2qkqjto6n2qio0h7/66360713344.pdfIn PDF document text
    • http://qzgj.cn/upload/file/sifow.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/3bdfef3ed1ffe51395232bbfb3fa7c0a/26909840606.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ba191842bd7---35603395990.pdfIn PDF document text
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/f750b648fb29698f655a82015b1ad93a/35277965915.pdfIn PDF document text
    • https://yuss.it/file/75056612442.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=report+card+comments+for+nursery+pupilsPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ded6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDED6 5412 bytes
SHA-256: a1cb4c4b015aef7fae0baf78172c628fce87d6d7200e98e44ff8178f715c390d
font_01_sfnt_off0000f138.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF138 10548 bytes
SHA-256: 6816912a0757710b302caac98721e7f37e2331a4b395cf522050325acd90e815