Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4aac42daa942693…

MALICIOUS

PDF

78.2 KB Created: 2021-09-18 15:46:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 8af73d90e413b3b6df9fb3534ee99bf2 SHA-1: dd9ae716c6b1571c3f07243334ed12dfb8a6d722 SHA-256: b4aac42daa9426935a4716a2e061932dbb930dafc704e41ce1e84117dccf189a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm, directing users to numerous distinct hosts, which is a common tactic for phishing or malware distribution. Although no scripts were extracted, the presence of embedded URLs and the link farm behavior strongly suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 http://eastendmediation.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/ganotoxekosodisomati.pdf In PDF document text
    • http://chiaranannini.com/userfiles/files/74554221526.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/mixijafasal.pdfIn PDF document text
    • http://saktigroup.in/uploads/68119918733.pdfIn PDF document text
    • http://jinistudy.com/_UploadFile/Images/file/71723346124.pdfIn PDF document text
    • https://groupunsur2.com/contents/files/51158812400.pdfIn PDF document text
    • http://hockeydh.com/files/ups/files/rixokeporolomujiduruwiruj.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/kupipelanitiwabukoto.pdfIn PDF document text
    • http://movietek.vn/hinh-anh/files/5109501745.pdfIn PDF document text
    • http://daearesort.com/FileData/ckfinder/files/20210913_039896173B9A670E.pdfIn PDF document text
    • https://mandarinusa.com/userfiles/file/1630885878.pdfIn PDF document text
    • https://cvsc.co/userfiles/file/1382117320.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/2vakamut70joqgh63ldftm6arb/29766689387.pdfIn PDF document text
    • http://csigikes.hu/admin/fck_upload/file/24528534084.pdfIn PDF document text
    • https://heks-tech.com/app/webroot/userfiles/files/wosasefapasovedid.pdfIn PDF document text
    • http://kagoshimakojintaxi.com/userfiles/file/57663816544.pdfIn PDF document text
    • http://hondatayho.vn/images/ckeditor/files/17380407422.pdfIn PDF document text
    • http://dom-2000.ru/ckfinder/userfiles/files/zogasitobozoke.pdfIn PDF document text
    • http://stin-verdon.fr/assets/Image/files/varizegosatipupipiwir.pdfIn PDF document text
    • http://ydtmuhendislik.com/ckfinder/userfiles/files/lidurudagapotipobevufod.pdfIn PDF document text
    • http://quinta.cl/upload/files/wawajazi.pdfIn PDF document text
    • https://ngaa.org.au/application/third_party/ckfinder/userfiles/files/67690198344.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/kabajax.pdfIn PDF document text
    • https://psg66.ru/admin/ckfinder/userfiles/files/dirasatim.pdfIn PDF document text
    • http://kimwendelldesign.com/ckfinder/userfiles/files/86426364151.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+transfer+data+from+mobile+to+laptop+with+cablePDF link annotation
    • 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_off0000cb5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB5B 11104 bytes
SHA-256: ca160ba7b6ad02f926fada49f4bebe85ac00d885b2e34deab4b8e2437a9cf343
font_01_sfnt_off0000e4d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D0 17780 bytes
SHA-256: 384d0b854bb29cab2d23800f16926217c8190e18723d85e553d87b77b8b08611
font_02_sfnt_off000112c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1