Malicious PDF — malware analysis report

Static analysis result for SHA-256 de98dd7221eabbe5…

MALICIOUS

PDF

71.6 KB Created: 2021-10-01 16:04:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: dc36442fb4bfcdee2df2d7b229d6cf17 SHA-1: 1833453e63cbcc7a83cee9b8d5947bb170b8eea8 SHA-256: de98dd7221eabbe58e882c76e59b43c445e677b6c7c3926cd0c34a7739d42627
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many pointing to link farms hosted on disposable domains, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://polenhosting.com/calisma2/files/uploads/gapizapu.pdf In PDF document text
    • http://pdww.ru/ckfinder/userfiles/files/42389188255.pdfIn PDF document text
    • http://khmim.com/ckfinder/userfiles/files/1746689891.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131865e339fd---925053020.pdfIn PDF document text
    • http://xn--o39a91gvwm83kbsn.com/FileData/ckfinder/files/20210917_F4318FBAF07E3CAC.pdfIn PDF document text
    • http://dreamwith.gni.kr/ckupload/files/29839421304.pdfIn PDF document text
    • http://elitacasa.it/images/file/31188076657.pdfIn PDF document text
    • http://dijladentalcenter-qa.com/userfiles/file/26264611644.pdfIn PDF document text
    • http://biancoacolori.it/userfiles/files/97892199870.pdfIn PDF document text
    • https://banderlogclub.ru/Files/file/87368748542.pdfIn PDF document text
    • https://ladachess.ru/userfiles/file/16088545976.pdfIn PDF document text
    • https://jackinthegymtpe.com/uploads/files/202109250222514243.pdfIn PDF document text
    • https://madame-tina.com/ckfinder/userfiles/files/1661290080.pdfIn PDF document text
    • https://bandotrading.it/uploads/file/nidewedurominogoboxaxirum.pdfIn PDF document text
    • https://duongthuy.net/userfiles/file/49777927411.pdfIn PDF document text
    • https://comillaspostgrado.es/userfiles/file/lelajoxumekabetes.pdfIn PDF document text
    • http://bolt.fo/public_html/userfiles/files/noxosofedatujirekadeveve.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/maxedazosirelone.pdfIn PDF document text
    • https://pleasanton.com/wysiwygfiles/file/xojorilududuxaxejogoxuzoj.pdfIn PDF document text
    • http://brezov-gaj.si/uporabnik/file/tanolatesaxamaxexavu.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/67960678516.pdfIn PDF document text
    • http://lica-mpt.it/userfiles/files/3987840836.pdfIn PDF document text
    • http://gibkrakow.pl/uploads/files/ratiwufowemow.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/68158023469.pdfIn PDF document text
    • http://hnkingdee.cn/Files/file/202191014302.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1613434f8e4864---87984400866.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=wii+new+super+mario+bros+romPDF 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_off0000b525.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB525 17148 bytes
SHA-256: 1e3ef6c7ad3c255c7c7f7b0432684cdefa7968d6d05629c9a49621671b13789d
font_01_sfnt_off0000e081.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE081 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f898.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF898 10588 bytes
SHA-256: a6ba774563eb6cc7f22dff502ce19768350ea7c281d93b0ec0d4b5034898a790