Malicious PDF — malware analysis report

Static analysis result for SHA-256 737344a9b18bfa5e…

MALICIOUS

PDF

69.9 KB Created: 2021-09-26 18:52:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: abf086bf9f78639bbf5a1ba5f344c02e SHA-1: 5003eea9d1487f95a530a6766b5c8a4873c2fc02 SHA-256: 737344a9b18bfa5eac1d0fab46f25bb0287f916a3fae21be7a88797024ad3a13
156 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 numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics suggest this document is part of a phishing campaign, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://irlanc.ru/uplcv?utm_term=pixel+4d+live+wallpaper+apk PDF link annotation
    • http://investin-khj.ir/ckfinder/userfiles/files/podunebowoxebe.pdfIn PDF document text
    • http://capital96.com/userfiles/file/lewevamedalopifuluwu.pdfIn PDF document text
    • http://iiiemjobs.com/FCK_Editor_Images/files/damomikuminow.pdfIn PDF document text
    • https://texasbordervolunteers.org/userfiles/file/jaboranuvamep.pdfIn PDF document text
    • http://nhatrangpalace.vn/app/webroot/upload/files/29274860875.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/4993f007100d486c62b38e5f4950e6ea/paxewumaxidete.pdfIn PDF document text
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/bld7ha43d1oeo9qjlqgp9hknh6/vusujizugumefinojerani.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/21255871908.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/niwidopowibevi.pdfIn PDF document text
    • https://texasbordervolunteers.org/userfiles/file/79976905926.pdfIn PDF document text
    • http://adriennemason.com/assets/files/11346858118.pdfIn PDF document text
    • https://elnativocoffee.com/silver/upload/files/bobumusevosazenoza.pdfIn PDF document text
    • http://buren-kompanie.de/userfiles/files/96477635877.pdfIn PDF document text
    • https://semineebrasov.ro/printuri-fi/files/59232307943.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/15f6c1db7284643f6bfa4bea7004ad12/fupinirapuloluvolisavoxub.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614e05d8c9679---kudepibojaguf.pdfIn PDF document text
    • https://dalnoboy.com/data/filestorage/upload/files/97337263527.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/2m7vpf7v9t6fjbq177kipng81j/91044329791.pdfIn PDF document text
    • https://clinicamanila.com/ckfinder/userfiles/files/36112877840.pdfIn PDF document text
    • http://zhouzhuanx.com/v15/Upload/file/2021924111452160.pdfIn PDF document text
    • http://www.ruben.pl/ckfinder/userfiles/files/64133089779.pdfIn PDF document text
    • http://sp2wronki.pl/fotki/fotki/file/pixizagovutigu.pdfIn PDF document text
    • https://b2cdemo.tickets.com/content/files/gazumogelib.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_off0000b079.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB079 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c890.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC890 10320 bytes
SHA-256: a19d1f4899ddcaa99a4163949ad80cafddcea17e1c042992c6bcf48b7980a309
font_02_sfnt_off0000e000.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE000 16468 bytes
SHA-256: 5ae77f1eed0df2dba28aa8285c25df7f1511bf84eaad3608143254dbeac7931b