Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4e551567d841bc6…

MALICIOUS

PDF

80.9 KB Created: 2021-09-09 06:35:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: eeff135c67b77e665c0cfae997b86b3b SHA-1: 0263ab93b54df65c91def29bc05b4ed1c6d54a04 SHA-256: c4e551567d841bc65729c782c531fb234c1b65d04a4f3968fb66a334c1606b05
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, presenting numerous links to potentially malicious PDF files hosted on various domains, likely to trick users into downloading malware. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://ronaldtan.nl/images/photo/55896567369.pdf In PDF document text
    • http://topup-fight.com/ckfinder/userfiles/files/30262595816.pdfIn PDF document text
    • http://yusungchart.com/userData/board/file/92960636256.pdfIn PDF document text
    • http://gezond-trakteren.nl/kasteel-doornenburg-img/bestandenfile/sidina.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/4973d8e8d8df1f421528d3fb5665c164/laxalolusina.pdfIn PDF document text
    • http://0975811252cool.linker.tw/files/34151231750.pdfIn PDF document text
    • http://serbanindustrialconstruct.ro/uploads/files/kufawidopupob.pdfIn PDF document text
    • https://sunnyrosesschool.com/userfiles/file/92724970512.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/1872834443.pdfIn PDF document text
    • https://asset-books.com/userfiles/file/dusasolewuwaxifofuves.pdfIn PDF document text
    • http://yogathoitrang.com/quangbasanpham/app/webroot/upload/image/files/dezodofubuludezijivor.pdfIn PDF document text
    • http://sdes.in/uploads/waxivudekitodasadafi.pdfIn PDF document text
    • https://muzpony.de/obrazki/file/12546334782.pdfIn PDF document text
    • http://hoachathoanggia.com/userfiles/file/mijidagopalibupefuma.pdfIn PDF document text
    • https://ladulceseguros.ar/noticias/fckeditor/file/xibonolimarepitofipobop.pdfIn PDF document text
    • http://morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613934a2e1e4d---wejovamalafaxok.pdfIn PDF document text
    • https://kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/lizimir.pdfIn PDF document text
    • https://kme.pl/global/app/webroot/uploads/file/16307649393498.pdfIn PDF document text
    • http://orenprom.com/img/account/file/xopewarun.pdfIn PDF document text
    • http://fireprovietnam.net/luutru/files/gewivekap.pdfIn PDF document text
    • http://cuanhuaabshanquoc.vn/files/resagitopuguzibarobate.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/55234727628.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=pokemon+xy+ds+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_off0000d6df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6DF 10320 bytes
SHA-256: 508b78f5c1e8d6462a9697e576d66ddfd47169e9847a11834aed3f7dbd8121a0
font_01_sfnt_off0000ee28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE28 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001063a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1063A 18716 bytes
SHA-256: afe7e748eed49983790698db7e44c3153d68c6274550ba21e25aa02cbb14140a