Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb227ce41491216b…

MALICIOUS

PDF

69.3 KB Created: 2021-09-15 12:58:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 04ac926a44926698dc792bcc37bcbe73 SHA-1: 4ab8fe88d16e8cf104cb95621f18f66d0f4e8dae SHA-256: cb227ce41491216b6387cb39b02d5820801fcbf3f62d880d5e8613a69b2c5bd4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm on disposable hosting. The embedded URLs, such as 'https://kingwaterpure.com/ckfinder/userfiles/files/53380564367.pdf', likely serve as lures to phishing or malware distribution sites. No scripts were extracted, but the PDF structure and URL patterns suggest a phishing or credential harvesting attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kingwaterpure.com/ckfinder/userfiles/files/53380564367.pdf In PDF document text
    • https://trystsalonri.com/images/file/15025377864.pdfIn PDF document text
    • http://konditsionery-zheleznodorozhnyi.ru/upload_picture/file/wedinivufuwag.pdfIn PDF document text
    • https://posaonakosovu.com/ckfinder/userfiles/files/zivunawokukazusefumuda.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210905152840.pdfIn PDF document text
    • http://siamintertrade.com/file_media/file_image/file/65300753055.pdfIn PDF document text
    • http://freeorden.com/media/file/binod.pdfIn PDF document text
    • https://arnetbilgisayar.com/upload/ckfinder/files/miwanerijenotupak.pdfIn PDF document text
    • http://orlickachata.cz/files/files/lawizulagesafukituwevojit.pdfIn PDF document text
    • http://songpinhao.com/userfiles/files/98246298865.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/zurozebazepotuzakopuw.pdfIn PDF document text
    • https://ratosatu.com/contents/files/90672103310.pdfIn PDF document text
    • https://lochoanggia.com/upload/files/makibapobimajipagosafe.pdfIn PDF document text
    • http://spec-so.ru/sites/default/files/file/52140550934.pdfIn PDF document text
    • https://triosms.com/userfiles/file/jonide.pdfIn PDF document text
    • http://ofitecnic.es/files.ofitecnic/fck_up/file/43444209922.pdfIn PDF document text
    • https://hoavily.com/uploads/files/74420457976.pdfIn PDF document text
    • http://mopi.eu/ckfinder/userfiles/files/wufop.pdfIn PDF document text
    • http://teranor.com/ckfinder/userfiles/files/xulijodesutomeduwupofax.pdfIn PDF document text
    • http://poslovniimenik.net/firme_data/files/69753011843.pdfIn PDF document text
    • http://paulgraphics.paulsfashion.in/files/10880772039.pdfIn PDF document text
    • http://villalapinetafavignana.it/userfiles/files/banogeda.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/161319247195f9---xitigenepuvebev.pdfIn PDF document text
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/52823368133.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=no+recent+apps+showingPDF 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_off0000b340.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB340 10672 bytes
SHA-256: 09b0ab1d2cba7a2e830dc23c879a1def8f7eb527579efd8a54b5266e2c367f97
font_01_sfnt_off0000cbbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBBC 14356 bytes
SHA-256: 150512030ee5a6400793282653bf2881999adc84446e423f491281d8566f1d72
font_02_sfnt_off0000ef69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1