Malicious PDF — malware analysis report

Static analysis result for SHA-256 99df6bb36d80e2b2…

MALICIOUS

PDF

81.8 KB Created: 2021-09-11 19:04:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 1e4d8b488723f768a840c5396ea9a9bb SHA-1: 4e09c8454cdb93178805a96552669fa306774406 SHA-256: 99df6bb36d80e2b2c5f4564d45fe9ba4aa97233e0760aac978177fd415117f72
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, including links to compromised WordPress sites, indicating a malicious intent to redirect users. The ML classifier and ClamAV detection strongly suggest malicious activity, likely related to phishing or malware delivery through a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/ka3i7vvd0fi6lfn0oi0ha5tis5/vejusojane.pdf In PDF document text
    • http://fotografieindex.nl/images/uploads/64654076801.pdfIn PDF document text
    • http://cloudinfo01.smartevolve.com/images/ckeditor/files/pomove.pdfIn PDF document text
    • http://anhhieu.vn/hinhanh/file/20073236548.pdfIn PDF document text
    • http://debeight.net/UserFiles/File/pemira.pdfIn PDF document text
    • https://candica.pl/ckfinder/userfiles/files/58095164070.pdfIn PDF document text
    • http://bassonconsulting.mc/userfiles/file/34953631296.pdfIn PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/50477508294.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/1b6f43282865d3dc2a21f68b61314907/rudazawuvasobasisopori.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/dedipegaguguj.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613413e47fbb1---xixeretupogiv.pdfIn PDF document text
    • https://bccphil.paramedix.biz/uploadfiles/file/zilobibuda.pdfIn PDF document text
    • http://nawoo.net/userData/board/file/xixilujopu.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613923810a477---dupugemalozolawozere.pdfIn PDF document text
    • http://contrast.no/ckfinder/userfiles/files/86195669279.pdfIn PDF document text
    • http://jinsonmetal.com/Upload/file/jewuvapokafijoxudezozu.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/066f7fbba5ba77b1c79a2a4aabed1f69/dapalekadefedefepumanog.pdfIn PDF document text
    • https://manhremhoangvan.vn/wp-content/uploads/files/fitevagasibu.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/d6293ecf73a70a94dc64902b0b93d2fb/gadovanis.pdfIn PDF document text
    • http://hglobaltour.com/FileData/ckfinder/files/20210905_029D83CB600395F7.pdfIn PDF document text
    • https://bitree.com/ckfinder/userfiles/files/gigaxawesitimi.pdfIn PDF document text
    • http://conservativista.com/js/ckfinder/userfiles/files/28025040142.pdfIn PDF document text
    • https://nulifeus.com/~nulife/userfiles/file/56756763922.pdfIn PDF document text
    • http://usateatop.com/_upload/files/27443281968.pdfIn PDF document text
    • https://www.liftechforklifts.com.au/application/third_party/ckfinder/userfiles/files/tuvasej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=htc+touch+diamond+romsPDF 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_off0000da25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA25 10548 bytes
SHA-256: 58e6b1d81806fcf677c411775488b3d51f8b706c8fcd02338eac27ea5e7ac84c
font_01_sfnt_off0000f1f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F5 18320 bytes
SHA-256: b11a2be53449ad14f366e75ccfa10edbe3e45d0fb48f96a77622e6e49396c1d9
font_02_sfnt_off000121ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1