Malicious PDF — malware analysis report

Static analysis result for SHA-256 c856709358bb6f7f…

MALICIOUS

PDF

81.8 KB Created: 2021-09-18 09:29:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6d7919a09745ad03de85870dae9fd0b0 SHA-1: 79ccd73d65163a906cb97954d0bef162fa1ab9f4 SHA-256: c856709358bb6f7fe3af6c831dae4529500682dec646710a8d630815f08effd0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links, a common tactic in phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://mousike.it/img_ins/files/59026564783.pdf In PDF document text
    • http://mrcubezpieczenia.pl/app/webroot/media/files/56686439780.pdfIn PDF document text
    • https://middletonchambers.com/ckfinder/userfiles/files/11714489351.pdfIn PDF document text
    • https://airin.lv/images/userfiles/file/43051062081.pdfIn PDF document text
    • http://xn----7sbbgprpk7biiq.xn--p1ai/admin/ckfinder/userfiles/files/38842866998.pdfIn PDF document text
    • http://bridgestone-ice-cruiser-7000.ru/ckfinder/userfiles/files/18614006399.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/24695408672.pdfIn PDF document text
    • http://dezis.ru/uploads/files/52531183221.pdfIn PDF document text
    • https://sukienmiennam.com/userupload/files/nudinaxunemeputapeliwovu.pdfIn PDF document text
    • https://eksiliotomotiv.com/upload/ckfinder/files/fomowikezuja.pdfIn PDF document text
    • http://hongsung114.com/files/fckeditor/file/76772719798.pdfIn PDF document text
    • https://www.zaantraining.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16136b77a5ac04---takutifasifit.pdfIn PDF document text
    • http://upasamed.org/Content/uploads/files/wunesivoduwiv.pdfIn PDF document text
    • https://jagamimpi.info/contents/files/39249619105.pdfIn PDF document text
    • http://learnersdigest.org/userfiles/file/vupelizixibaf.pdfIn PDF document text
    • http://scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/tumopesemoseb.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/pozubelajevigowabute.pdfIn PDF document text
    • http://weifong.tw/fckimages/file/dazepoxomokodov.pdfIn PDF document text
    • https://aynadakikemalizm.com/resimler/files/rinebotutaves.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021090620253793.pdfIn PDF document text
    • http://heyumpnd.com/userfiles/file///tuwavamiru.pdfIn PDF document text
    • http://mezon.jp/userfiles/file/4394571948.pdfIn PDF document text
    • https://panelshock.com/userfiles/file/wofavetakiwubimabi.pdfIn PDF document text
    • http://akcihlar.cz/userfiles/file/mafuvomuv.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/51eeac32516e4a335891deb370e9bd52/2347884553.pdfIn PDF document text
    • https://ewastexperts.com/userfiles/files/puvutivo.pdfIn PDF document text
    • http://groupkaishan.com/d/files/25591363646.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=watch+free+basketball+gamesPDF 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_off0000dcd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCD9 17020 bytes
SHA-256: 4bdfff81d9e1ed6b60632adcbf607f8ba41a79eedd660742cad341bd2417801e
font_01_sfnt_off0001086e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1086E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012085.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12085 10692 bytes
SHA-256: c893fa2a17bad87ae5d5a8c0819168f7d426eaf6a90d7c76b5f7378202035b43