Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f5ac85d3f4e95dc…

MALICIOUS

PDF

81.7 KB Created: 2021-09-10 04:31:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f6ab6ba3a40ec2eaf51a86bb0028cd02 SHA-1: f34e2f0885f4b1b20dd97142f8f8bdc02f01911b SHA-256: 4f5ac85d3f4e95dc90283e109127a4e8c60747d2e1a5635a53f5832f54dd009c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs pointing to disposable hosting, suggesting a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and numerous external links indicate a phishing or malware distribution attempt, likely leveraging embedded JavaScript for execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://smidgel.ru/uplcv?utm_term=best+browser+for+old+android PDF link annotation
    • https://trinityautorepairs.com/uploads/files/xejavemega.pdfIn PDF document text
    • https://projectmine.hu/ckfinder/userfiles/files/mawipuvipelanavol.pdfIn PDF document text
    • https://serviceelectric.ca/userfiles/file/gifusowupisozulupibim.pdfIn PDF document text
    • http://huyndaicaudien.com/upload/files/tuxugovejevoduxud.pdfIn PDF document text
    • http://sun-green.de/ckfinder/userfiles/files/buzeri.pdfIn PDF document text
    • http://dealershop.es/camarasegovia/userfiles/file/8831189856.pdfIn PDF document text
    • http://belean.pl/userfiles/file/10193886878.pdfIn PDF document text
    • http://lnhaihui.com/userfiles/file/20210907073306_221236362.pdfIn PDF document text
    • https://mallorcaboom.com/res/wysiwyg/file/45739817279.pdfIn PDF document text
    • http://jsqnchem.com/upload/files/16217377974.pdfIn PDF document text
    • http://envisystem.com/upload/userfile/files/duxabovudomumevivodam.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613762cd6141d---nolekokemovile.pdfIn PDF document text
    • https://laurallo.com/ckfinder/userfiles/files/sodoxoxita.pdfIn PDF document text
    • http://marathon-gexin.com/Uploadfiles/files/nopikugosobewameli.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132727c5d603---29161695078.pdfIn PDF document text
    • https://cli-kh.com/uploads/files/202109052210157963.pdfIn PDF document text
    • https://jaurrieta.net/USERFILES_JAURRIETA/files/patebutis.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021090406455481.pdfIn PDF document text
    • http://twfbs.com/ckfinder/userfiles/files/64187832896.pdfIn PDF document text
    • https://ienter.bg/files/2685435905.pdfIn PDF document text
    • https://villanakarin.com/userfiles/files/16443730692.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/16131395643ba3---6332516172.pdfIn PDF document text
    • http://mega-treid.com/userfiles/files/lesazipoziniregosejipipew.pdfIn PDF document text
    • http://iglozawiercie.pl/zdjecia/file/zujusuwiw.pdfIn PDF document text
    • http://abwplazaview.com/uploads/files/42164286709.pdfIn PDF document text
    • https://mediaget.com/userfiles/files/lisesuliw.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_off0000d93a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD93A 10628 bytes
SHA-256: 0a6b17ff34e5c11b9c197b54cf4ea50d2e20678d592f71a7bf39c7287e257d26
font_01_sfnt_off0000f1c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109D2 18376 bytes
SHA-256: 4c98feaa5d92b7b34397f4b1733ef65104bc12823cd9d5d299663a9850f66882