Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3188ce949774f1a…

MALICIOUS

PDF

64.3 KB Created: 2021-09-07 16:33:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b9408003a4c737270ff609b4374e62a8 SHA-1: ab443a4be69cfbc80920cdc1067640917aabb60e SHA-256: a3188ce949774f1adcd3a695735de04183ea5445ea1abf2cbccd6d808d926777
72 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites hosting further PDF files. The embedded JavaScript stream, while not directly readable, suggests an attempt to execute code or further exploit the user. The overall structure indicates a campaign to distribute malicious content through a chain of redirects.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4625

Heuristics 5

  • 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
  • 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://nguyenthaotech.com/upload/files/95918483126.pdf In PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/64214b0689109569e9d46735dc078311/26748863483.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/23550472861.pdfIn PDF document text
    • https://bibliothequedesarts.ch/ckfinder/userfiles/files/80285300298.pdfIn PDF document text
    • http://the100voicesofgospel.de/fichiers/newsletter/file/duxufevawumomitub.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdcc94a7cad---22876302735.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a78636ab813---76660778769.pdfIn PDF document text
    • http://anninh247.info/upload/files/72628107356.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/15897966019.pdfIn PDF document text
    • http://studiogallerani.it/userfiles/files/85915365133.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/85419186986.pdfIn PDF document text
    • http://businessvaluationapp.com//fck_files/file/49950631159.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609f85088e4ff---19386480772.pdfIn PDF document text
    • http://bjzjygj.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/fefuwutoxogobusi.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/350590fdfb0c91bbdbeb63fd2a728eea/92089529586.pdfIn PDF document text
    • https://jagominum.com/contents/files/xirigosabejamixi.pdfIn PDF document text
    • http://arserwood.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210807023618533252argdu2.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16073e6a91b48e---68799246119.pdfIn PDF document text
    • http://megatex-plast.ru/pub/file/lujalaleriledesopi.pdfIn PDF document text
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/dfd1c6e7ac49466e692b95fd7cbb3ac4/ligabij.pdfIn PDF document text
    • http://feuerwehr-mittenwalde.de/mediathek/files/mabokunubivuzoxiputukekir.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/9vhefl7q86cvlatghhlf4qib2b/39763672260.pdfIn PDF document text
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/0ae3f9c3590a087b98b809b09e5a27ed/vuxov.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=pwc+global+entertainment+and+media+outlook+pdfPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cb49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB49 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e360.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE360 11212 bytes
SHA-256: 02ad2795ef62efe27cb74f023ffd737f59ab458284b9be4fb458ce6c7748178c