Malicious PDF — malware analysis report

Static analysis result for SHA-256 d821a9e6a1fb4b25…

MALICIOUS

PDF

69.6 KB Created: 2021-06-06 22:28:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: f01727d9b36e5e1bb09839b73caec3ac SHA-1: 08447ce72599537471b3bffc508d386446546090 SHA-256: d821a9e6a1fb4b25b392f53843aac3b9d17d29696e283b6ec069ed23b93ea022
156 Risk Score

Malware Insights

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

The PDF file contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to redirect users to potentially harmful content.

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 https://oniceh.ru/uplcv?utm_term=android+9.0+samsung+s6+edge+plus PDF link annotation
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/1adp1kvc8udnlhks1svhgvno67/3353065854.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/94f7ad763095c10071d06e362dd853e0/wesibakedu.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/77201174004.pdfIn PDF document text
    • http://plncse.hu/php_data/file/57741830056.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/16096bf47d28e5---89655981710.pdfIn PDF document text
    • https://lawina-radom.pl/files/file/95071820291.pdfIn PDF document text
    • https://majorsagilekvaros.hu/uploads/file/kedizaxudoduwubi.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/h8rd38a9iqj3i4hamm5u3jmn2c/sefoxajutamamapuvob.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/fc8vpfkbhe2040e3lcvrtgag0b/gizemizamujubexuzup.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607e84fceab4d---62637859880.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1af1422dc6---gukimatoxavogejopoxarute.pdfIn PDF document text
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/2lb6ce60im6geb0u9rii1neikf/pemopigekisulokojut.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0eb622bf35---loridulukozabone.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/sinuti.pdfIn PDF document text
    • http://mobilephleb.com/clients/2/2d/2d2188d13063160162e6e2bbcdac547d/File/gumoramituwe.pdfIn PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/17fecfa291028d8053503e0a32a16461/32391319310.pdfIn PDF document text
    • http://terminsk.by/pics/files/rinob.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_off0000d435.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD435 5752 bytes
SHA-256: 88c02cfaab54744d6f709d93e9c435c4416032061781fbdda496b2748b16a258
font_01_sfnt_off0000e7b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7B0 9864 bytes
SHA-256: 3e84e38d669ca3131e5c12ffa9be002ed52b1f1fb2edc45dbe2956b57fc2af43