Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd8bec3fc0b727b6…

MALICIOUS

PDF

76.4 KB Created: 2021-09-13 03:21:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 4e36ee4404c7a041b285eb59a6d8ce70 SHA-1: 37b836e36f5df932035783ec19319e2c9d25c234 SHA-256: cd8bec3fc0b727b65db1bb7da917a1baf41e32f0cb7a6822f2f9025461c18684
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is designed as a link farm on disposable hosting, suggesting a distribution or phishing lure. While no scripts were explicitly extracted, the nature of the PDF and its embedded URLs point towards an attempt to redirect users to malicious content or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://train-in-japan.com/images/blog/file/74287155479.pdf In PDF document text
    • http://nayyaralidada.com/alpha/ckfinder/userfiles/files/xosezedupabigetelezunazum.pdfIn PDF document text
    • https://xn--fct5g39pjpo.tw/upload/leakstop/files/zaruva.pdfIn PDF document text
    • http://tplustech.com/images/ckeditor/files/52902945274.pdfIn PDF document text
    • https://drhuanghair.com/uploads/files/202109031558122702.pdfIn PDF document text
    • http://eternaseguros.net/files/files/poleduvilanemirisumak.pdfIn PDF document text
    • https://tims.ro/ckfinder/userfiles/files/sobuvopirugalesemixabi.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/bapagisas.pdfIn PDF document text
    • http://anduong-nhatthanh.com/uploads/news_file/jiwapemovexudobiluba.pdfIn PDF document text
    • http://exclusivelimoservice.com/ckfinder/userfiles/files/39613275922.pdfIn PDF document text
    • http://kukdae.com/files/fckeditor/file/tofal.pdfIn PDF document text
    • https://houstoncoinshow.org/FCKeditor/file/68178314439.pdfIn PDF document text
    • http://monticellotownship.org/userfiles/file/23210814335.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/68257914315.pdfIn PDF document text
    • http://zoekidsworld.com/userfiles/file/bibenowubosizugazunafo.pdfIn PDF document text
    • https://dolupin.com/calisma2/files/uploads/309023585.pdfIn PDF document text
    • http://firegallery.ru/img/upload/35437746051.pdfIn PDF document text
    • http://christmaslandint.com/userfiles/95357094922.pdfIn PDF document text
    • http://mariautonoleggiomarsala.it/userfiles/files/73375531901.pdfIn PDF document text
    • https://narellesastro.com/userfiles/files/saraxulasig.pdfIn PDF document text
    • https://viadagio.be/userfiles/file/42527348722.pdfIn PDF document text
    • http://wirheiraten.de/images/file/10145121803.pdfIn PDF document text
    • http://alotercuman.com/ckfinder/userfiles/files/99066884411.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/9313062415.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=motorola+fastboot+commandsPDF 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_off0000c6e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6E6 10544 bytes
SHA-256: fea421fa28a045e075affc3b1f6b558713f2c7303b2db39d9af55838583b8062
font_01_sfnt_off0000defa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEFA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f70c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF70C 17124 bytes
SHA-256: 189afa26ae41ddbb547849af068793334c49a7ab30ada39cefcc07afbe33d48f