Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea81e5d3cb8de633…

MALICIOUS

PDF

100.6 KB Created: 2021-08-29 09:50:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 94eb863977a5a4aa9fd5856931338d45 SHA-1: ddac3d4a5a0e00c486f29fa5a908983a85f9128a SHA-256: ea81e5d3cb8de63359b9310e2a22edbe688cbdd336d9dec4fda48383bcb606e8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is unreadable, but the heuristics and URLs are sufficient to infer a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 6

  • 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.
  • 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://kaupa.cz/userfiles/file/43184715094.pdf In PDF document text
    • http://goldmustang.com/files/files/gagiburikipogafapotamubu.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/dik2fa6qomlvbr5h555bl52dt6/81371628670.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/16083f19027d74---44336024991.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160831011f1928---37974309761.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/161002969d66c0---fawitevub.pdfIn PDF document text
    • https://milsagliksen.org/upload/ckfinder/files/53671342744.pdfIn PDF document text
    • http://herculesestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/82715814206.pdfIn PDF document text
    • http://cioccolatogallucci.it/userfiles/file/jujubevofobavipowe.pdfIn PDF document text
    • https://narimasu-chintai.net/jcfiles/file/rapififawisifa.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610e082846906---97810227081.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/67f641d2d224491f12dd6264081b89a7/lewilujiwizomiwiwagodi.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/ftqo5m8ndjvvue2o3eoo79kn4q/tidasedu.pdfIn PDF document text
    • http://sevennews.com.br/ckfinder/userfiles/files/32904296196.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/pabisuwikapekisesirer.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/da20f701ee8c01ea846f9d4455b733cf/jinogixejele.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/3716294648.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16102beb1f3904---nafibogajinurogazam.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b356902911c---62177618598.pdfIn PDF document text
    • http://bioident.pl/photos_fck/file/dudarerademukevemivibuj.pdfIn PDF document text
    • http://effektfilm.de/files/file/ponuwopupuji.pdfIn PDF document text
    • https://nodka.eu/ckeditor/ckfinder/userfiles/files/loxagemedam.pdfIn PDF document text
    • http://thallo-food.hu/uploads/ckfinder/userfiles/files/samuwu.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079248d6433e---wumilotiza.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/22defd106888a5dee9a5aa4698c2be67/doxugudenaro.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=a+particular+brand+of+dishwasher+soap+is+soldPDF 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_off00011e47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E47 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013659.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13659 19624 bytes
SHA-256: 22513286926caea09048040d17f34dffcd7ee61c58acc53289bb77580c6e43f3
font_02_sfnt_off0001699a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1699A 11024 bytes
SHA-256: b34b2cbaa75e26d0dcb04e2d9dc5a3ea6bd21640af59be79a97b537ffc2a880b