Malicious PDF — malware analysis report

Static analysis result for SHA-256 66ad9c917aa48229…

MALICIOUS

PDF

78.5 KB Created: 2021-09-04 23:18:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f748c4fcbef21412bc0d1b447ace0eb3 SHA-1: c42e71c695f42bf9d9f8d2777cb1357b1a5d27ba SHA-256: 66ad9c917aa48229d390cf89169c9f43379b0c572922cc5fc48ac6a92ce1ed7f
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the structure and heuristics suggest the PDF is designed to lead users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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.
  • 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 https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/7450458e7253563f7c5eab18c0580b74/zewaxogizixijaginigivamim.pdf In PDF document text
    • http://bakineshr.az/ckfinder/userfiles/files/14556513395.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/zizetutetidijas.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/jebubotoz.pdfIn PDF document text
    • http://martonelektro.hu/files/file/97833416147.pdfIn PDF document text
    • http://zavalinka.by/var/upload/file/lelaxexiwaso.pdfIn PDF document text
    • http://alisawedding.com/upload/users/files/19397380940.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8bfe6b5954---18089942541.pdfIn PDF document text
    • https://narimasu-chintai.net/jcfiles/file/80465225329.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160944496ebec1---24308583940.pdfIn PDF document text
    • http://sntaviator.ru/ckfinder/userfiles/files/zigonamivina.pdfIn PDF document text
    • https://iamtimeshare.com/userfiles/file/62430345332.pdfIn PDF document text
    • http://arci-mp.fr/admin/File/99661238360.pdfIn PDF document text
    • http://trunghungplastic.com/luutru/files/39242875334.pdfIn PDF document text
    • https://cosmopolitanhotel.eu/uploads/wysiwyg/files/kibomepovav.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/cc5e8e3f1f51a8371f524a1618ef9468/3944586709.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160cfca4b2825c---xinolidevoliritegal.pdfIn PDF document text
    • https://namratalakhotia.com/userfiles/files/46379196132.pdfIn PDF document text
    • https://cam-ceeds.org/ckfinder/userfiles/files/97422820709.pdfIn PDF document text
    • http://extintoresorigen.com/images/editor/61005302417.pdfIn PDF document text
    • http://np-laser.com/upload_fck/file/2021-7-14/20210714023319893575.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202105022232112812.pdfIn PDF document text
    • http://duoctruongxuan.vn/userfiles/image/file/xepoxomiril.pdfIn PDF document text
    • http://geluidsadviesnederland.nl/ckfinder/userfiles/files/98776911477.pdfIn PDF document text
    • http://surtek.biz/image/files/20150223_231353.pdfIn PDF document text
    • https://latrinquette.com/upload/editor/file/36724905529.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=whirlpool+washing+machine+manual+wwdc9440PDF 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_off0000cbd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBD9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e3eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3EB 17508 bytes
SHA-256: 66f6070a18e784d22dcfc60bed0f24a87596170b62976f6ab1b820bac9647496
font_02_sfnt_off0001114c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1114C 11412 bytes
SHA-256: 69cb78418003137fe2c5862f7b740f2fe6bc61138fcaf6e35236cd36349bb1cb