Malicious PDF — malware analysis report

Static analysis result for SHA-256 d36a06138fffc5a7…

MALICIOUS

PDF

81.0 KB Created: 2021-10-06 00:58:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: c041c0ddf01a3a9af6e78db94538050a SHA-1: 1974c2b5631e413be70a21bce054def4d44c5c17 SHA-256: d36a06138fffc5a73498c6cfd0cb7ff3503f402b1e96f0bcce1277cc3985edb1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript, which is a common technique for malicious PDFs to execute actions. The file also exhibits characteristics of a link farm, with numerous external URIs pointing to potentially compromised or disposable hosting sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://gaishachuukobuhin.com/js/upload/files/27752755647.pdf In PDF document text
    • http://2rent.gr/userfiles/file/juvokudafegedajolifosuwiv.pdfIn PDF document text
    • http://www.insight-assessment.com/ckfinder/userfiles/files/33933859017.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138dfa14d33e---33688265081.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/97638127578.pdfIn PDF document text
    • https://funbugs.ie/userfiles/file/66477253882.pdfIn PDF document text
    • http://ksiclubcom.ksiclub.org/svnprojects/DHD/Source/images/files/nigojijewavamafutizanad.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615cbdc4cb099---27185609723.pdfIn PDF document text
    • http://ebiocell.com/uploadfile/file///2021100106061540.pdfIn PDF document text
    • https://deverfgrossiercms.deindrukdemo.nl/upload/files/6897673580.pdfIn PDF document text
    • http://bluestandard.pl/ckfinder/userfiles/files/fusatapetavonapuvejov.pdfIn PDF document text
    • http://encino.ilovepokebar.com/uploads/files/91494490017.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/genoz.pdfIn PDF document text
    • http://manuale.aziendasulweb.it/userfiles/files/70697989032.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/lefodajupubumanazozajem.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/ab0fbaf24a79bf9e648dd0c1c6c2d6d3/laximuxazikonu.pdfIn PDF document text
    • http://dlshixiang.com.cn/ckfinder/userfiles/files/vazajiramiwujotaxonazegej.pdfIn PDF document text
    • http://studiotecnicoprato.eu/userfiles/files/befizal.pdfIn PDF document text
    • http://wimborst-ceramics.nl/ckeditor/ckfinder/userfiles/files/24060448725.pdfIn PDF document text
    • https://florissantdesign.nl/docs/Image/file/2846195519.pdfIn PDF document text
    • http://jhdljz.com/userfiles/file/1633366799.pdfIn PDF document text
    • http://sanruou.com/app/webroot/uploads/files/negawadisaxinazexavogi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+get+better+at+speaking+englishPDF link annotation
    • https://forum-auto.ru/data/files/In PDF document text
    • 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_off0000d5be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5BE 18148 bytes
SHA-256: 9466ea0e1804b53c967105c8a32c71ac0a19d9229d0aa4f3a1d586ded77d5d50
font_01_sfnt_off00010507.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10507 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D1E 10840 bytes
SHA-256: a8be965601056fef68e6921f958826c08268c83b9fb3074eab4b0c8cd901db4e