Malicious PDF — malware analysis report

Static analysis result for SHA-256 278650382416c72a…

MALICIOUS

PDF

94.4 KB Created: 2021-06-11 18:50:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 34c34e20cc79b17b1b40adb23461f2e8 SHA-1: 5e0d106b1b06edc30b47f9cf5518f4315e423cb2 SHA-256: 278650382416c72ad10121359cef6ddf33a77278efa0282b2ce365d7ed758b74
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites used for hosting the PDF itself. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for link farms, suggesting an attempt to obscure the ultimate destination or evade detection. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics strongly suggest a phishing or malware distribution attempt.

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://synerhu.ru/uplcv?utm_term=gloomstalker+dnd+beyond PDF link annotation
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/68e272bb1c7520ae8495a28dfae43792/pufexomiwigigaxorazuke.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090088e76b1e---71496176085.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a1bc6c149c6---25039179767.pdfIn PDF document text
    • http://insidethedigitaltrend.biz/userfiles/file/rexosafalosipumisitowed.pdfIn PDF document text
    • http://ingenermarket.ru/userfiles/fagidiruzidutedagonad.pdfIn PDF document text
    • http://goref.ru/files/file/896274612.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/5029ca400e4bb6369a4b6f94f39d2371/newitaxubosunejevebi.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/mnf1v54f6k09g78edvruurorm5/61128647187.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/61775557148.pdfIn PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/kle4g94ftatvj613vmac3kcgpc/13247489682.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160875b40563cb---lufinuzedaroluluzejitewa.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/as2fgn7hsfbkt7b1h770bugeb8/bosivifatenuli.pdfIn PDF document text
    • https://clifestyle.net/uploades/userfiles/file/53474172942.pdfIn PDF document text
    • http://podiummoda.ru/userfiles/file/fujugejakefibil.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/30389a7322cecdb4ec85e73f8a6e9f65/66817382853.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/be7782101c6dfdaf269ba892dff10cb7/53388997192.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/ae5280df72c1df4f047494f7bb2c1bf1/10108302617.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_off000134ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134AD 5308 bytes
SHA-256: 9a6956d7b62d0224148cdc42c0cee0ff696bd50d578ac3b68796789cc01d4653
font_01_sfnt_off000146ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146AC 10832 bytes
SHA-256: 883421d92d32bb922e2fb95b4d851b70d1b9774adfde6af55dbefb0351670ec9