Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb6fb5bb55d6f5b3…

MALICIOUS

PDF

76.5 KB Created: 2021-09-05 09:21:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3573649321ed6c03d144f70e2cb77b8b SHA-1: 6f918c4983b76a65189ce37d64d2dfc0331cd1c9 SHA-256: cb6fb5bb55d6f5b34910ae4c955969f1962a6c0e21a8937e61f2498ca81a4999
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://feldbach-tourismus.at/files/zuxinukagejeguba.pdf In PDF document text
    • http://ks-system.co.uk/ckfinder/userfiles/files/kafoliwaduluf.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/8376026797780cef06ae4dbaaf0869a8/liluxamafodikatore.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6ffcc9bbf6---lumajenowokige.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc8ff50166---relaxanana.pdfIn PDF document text
    • http://magyaringatlanadatbazis.hu/dev/_user/file/foxop.pdfIn PDF document text
    • http://erisalaw-chicago.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/girefuni.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/30c3f69eff864b59240bb3bd3867b309/webizetebaluditegava.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609570b83d692---58889797382.pdfIn PDF document text
    • http://giovanninociti.com/userfiles/files/todabotujotesomitoji.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-5-12/20210512030612807274.pdfIn PDF document text
    • https://emmaushuis.org/pages/43727142609.pdfIn PDF document text
    • http://lovesushiscv.com/uploads/files/26867668971.pdfIn PDF document text
    • https://aristi-trap.com/upload/users/files/42724947408.pdfIn PDF document text
    • http://theemasternetworker.com/ckfinder/userfiles/files/matitovunon.pdfIn PDF document text
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fd9be142255---48534857446.pdfIn PDF document text
    • https://kvkumariajnkvv.org/singhania/downloads/file/raxotosaduwi.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16112a707d2931---89300280043.pdfIn PDF document text
    • https://biocoils.com/img/file/lenomane.pdfIn PDF document text
    • http://imhyuk.com/imhyukeditor/userfile/file/jikibinokokitigav.pdfIn PDF document text
    • http://pcccphucvinh.com/upload/files/fedud.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/degawi.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/48322573790.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/45291438026.pdfIn PDF document text
    • https://octvads.site/js/ckfinder/userfiles/files/21683323905.pdfIn PDF document text
    • http://morard-mcf.fr/data/Files/54072642200.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=meal+prep+grocery+list+pdfPDF 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_off0000c5c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5C6 17572 bytes
SHA-256: 2c541801b146616492ffa33558498cce127a0287eef5fc62ae2a98e6e103b50f
font_01_sfnt_off0000f3c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C5 10796 bytes
SHA-256: 542f0cddb9db1d935c05402717af6ef9768040f175525b3344c3a8b3cf1aa213
font_02_sfnt_off00010c9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C9E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1