Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8337fd4bb000b36…

MALICIOUS

PDF

82.2 KB Created: 2021-09-20 19:21:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a663ea36efeeea5415d6bf4c647b8971 SHA-1: 56555731219c51b00c55398fbeb8a0f8105c00dd SHA-256: f8337fd4bb000b3624869c0a7913d4a0be8631d26973ffcce7f88a559ce401e9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload directories, suggesting an attempt to host malicious files or redirect users to phishing sites. The presence of a 'download button' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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.
  • 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://larrysiegellaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/37954785736.pdf In PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/8e5f995d02a779204b38d5b09a839745/gilalujixakotifisusatu.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/butubifulepewimoveza.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/db66afaf5a32716939b6df92a32ee7e9/buxanab.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16131d2527bd7a---marejemizifogox.pdfIn PDF document text
    • https://ceccargiurgiu.ro/userfiles/file/26915580699.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/70617630759.pdfIn PDF document text
    • http://templeton.sk/userfiles/file/dejurol.pdfIn PDF document text
    • https://websbag.com/uploads/files/lomipotove.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138f1c3de854---wovoseferele.pdfIn PDF document text
    • https://minjar.mebel18.com/uploads/files/79872292643.pdfIn PDF document text
    • https://togeltop.net/contents/files/domoxogixep.pdfIn PDF document text
    • http://pooq-design.com/app/webroot/fckfiles/file/52559411611.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/53236733963.pdfIn PDF document text
    • http://machulski.com/public/file/tagajaginupup.pdfIn PDF document text
    • https://home-consult.lu/userfiles/files/wipexabusujod.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613613e98b5d0---zotanujer.pdfIn PDF document text
    • https://verandapattaya.com/userfiles/files/11448808404.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/a36a3e7abb17d0dd5aa18c97a2ec08c4/55893319825.pdfIn PDF document text
    • http://katachizu.com/img/news/files/10244944772.pdfIn PDF document text
    • http://www.childofafrica.org/media/userfiles/file/vezujelizimowazemiger.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/vefafimulixabajegarusi.pdfIn PDF document text
    • http://7sate.com/filespath/files/20210919054847.pdfIn PDF document text
    • http://aunay-sous-auneau.fr/ckfinder/userfiles/files/33313282095.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16147d5f71e7b5---lenovobibu.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612f05d0e5f1c---33919037053.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=what+colour+do+you+get+if+you+mix+yellow+and+purplePDF 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_off0000dd2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD2E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f540.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF540 16888 bytes
SHA-256: 98155e788b8447d460f70be7a8927b310a46dbe0bb7cecfd83aad049f154a673
font_02_sfnt_off0001203d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1203D 11296 bytes
SHA-256: 4d1dd5dc3b5609ee15b8f9d1e190bec41925c13188cd939f371116be1a4beeda