Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a5c8d9f9f1ba582…

MALICIOUS

PDF

79.6 KB Created: 2021-06-19 16:23:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: d251eb2b78553625e8fbb9d98d53e129 SHA-1: af9677ab8847357eeb8432f4d7f0e33a5f782eab SHA-256: 9a5c8d9f9f1ba5828bd6a5fd02b33ac871da13cb4af67c9bda85f7c4b1b4a05f
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress upload directories, suggesting it is part of a link farm designed to host and distribute malicious payloads. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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.
  • 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://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609cb29de2b35---51403209850.pdf In PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6d363eb074---misefiloxubiputafufovexi.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/bd6d5afa1b9fb8821da955fba8a96d5f/laminimapaxinewelupavuvu.pdfIn PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/9eee7a0e5096da68500db8f3f47678fb/28421987951.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/52eb678479ca11d76b62d6e86b242fc1/2408053375.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/kofekamojobanozubife.pdfIn PDF document text
    • http://banghaija.com/userfiles/file/2144789143.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/63bfaf830ce736e5ab52983830fa39c9/zadebete.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/nfp11ptct6rq8lphfp4tchbjdu/91419803088.pdfIn PDF document text
    • http://cerezolorente.com/files/cerezolorente/_repo/file/72786529873.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa7d96a1977---13374463862.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/0v9f52oiui1ptrsk9afebc67c7/58124552627.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/39512338490.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/448812351c3d177971a45e4ab2a7c529/fomezasofipenunuper.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=zero+hour+short+story+pdfPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fc35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC35 4944 bytes
SHA-256: 41a73c0ec1c391d2f14747948dd6b28e2084a42678ca0918cb63acda9695da9f
font_01_sfnt_off00010d0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D0F 10784 bytes
SHA-256: 0d208f9c3303a33f56131f6ea16da0029d3e11121f41f3316a74d3e69aedaeb9