Malicious PDF — malware analysis report

Static analysis result for SHA-256 87b861d5b333b62d…

MALICIOUS

PDF

81.1 KB Created: 2021-08-27 00:52:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b19abaa66217a0eaa846bc3d67ed8554 SHA-1: 585167283dacf52131af587854cf0a8a56741bb0 SHA-256: 87b861d5b333b62d5908f08e2d0c55ab413145f275a3a4bd6423bad33924e403
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains. The heuristic 'PDF_RANDOM_URL_LINK' and 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly indicate a malicious intent to redirect users to potentially harmful content. The ML classifier and ClamAV detection further support the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

Heuristics 8

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=types+of+offer+in+business+law PDF link annotation
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/644jveb9nnnk2ahmhqonnn0q6q/75041956252.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c2eb0e61680---worusuzowu.pdfIn PDF document text
    • http://g-shocktou.com/user_file/file/72273158490.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606fd1e7dae1f---77351075340.pdfIn PDF document text
    • https://bursac.net/userfiles/file/remoza.pdfIn PDF document text
    • http://work4shop.cz/userfiles/file/66346992854.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/68538968352.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/f2f01b91b7327eb15f639a6a96ce3e14/mavetitifilarizififubel.pdfIn PDF document text
    • http://lambanghieuquangcaogiare.net/vietkiendo/upload/file/rutipik.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1608a7c7fcd0b3---bukiledakizuzuxativobo.pdfIn PDF document text
    • http://vodnik48.ru/content/file/18707240603.pdfIn PDF document text
    • http://danguykhoidoanhnghiephp.vn/Upload/files/57079688636.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/ribilev.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160d2c7e80ce87---79742788372.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/81951310103.pdfIn PDF document text
    • http://xn--80aafbladvtgxneccoge3bt.xn--p1ai/pict/file/3122443115.pdfIn PDF document text
    • http://umrllc.com/userfiles/files/98066479562.pdfIn PDF document text
    • http://dansecyr.ca/pdf/file/59537873622.pdfIn PDF document text
    • http://dienmaybaongoc.com/ckfinder/userfiles/files/66977385398.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/08/202108041642538371.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/24375938423.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/uc63ovq7umf21cutnmpt6diop6/tuxatujomawedukutu.pdfIn PDF document text
    • https://www.sensormaticltd.com/app/templates/js/ckfinder/userfiles/files/datelabafusum.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/q5ob1plok8e99h0es1hfgi64k0/fulaja.pdfIn PDF document text
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/8ad5a5e6fa5282c87f25e4d1edce1c55/muwotosixanubiladif.pdfIn PDF document text
    • http://www.village-gaulois.org/gestion/ckfinder/userfiles/files/71429258667.pdfIn 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://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_off0000dada.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDADA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F1 10656 bytes
SHA-256: c187e124d47fc595db360caf320bc1302716635e70a85501917daf8233ecf3c9
font_02_sfnt_off00010b4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4D 16488 bytes
SHA-256: 095e06a122497ccd4c632bd0d5fd3c70ee3eeef179ede180161578c458973be8