Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8a584f1b436e76b…

MALICIOUS

PDF

77.2 KB Created: 2021-06-18 14:45:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 5156477b9020fa8463e28653b32ab205 SHA-1: 53de8d2ce42def59317a0e5aef702f4196460a8e SHA-256: c8a584f1b436e76bc84e153e1f1618da13f1c27d418b364c059d83117d94daec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous links to compromised websites, many of which host other PDF files. The document body, though heavily obfuscated, appears to be a lure for popular content, suggesting a phishing or malware distribution attempt. The presence of multiple PDF link farms and the ML classifier's high confidence score indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/9ca8786b8c99ff3b880c2ab760966d80/nazug.pdf In PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607815adba41d---36316830212.pdfIn PDF document text
    • http://asijskepotraviny.cz/files/file/zuzol.pdfIn PDF document text
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/g9aqeaja8044ed7ii79tldpk89/97777064312.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1606c92520fe41---gawufuroda.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/940bd98e450ae10cb62345ffb0754f16/60464147767.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089b06f4a3d1---10354533955.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bfc0f7d5a02---10134829350.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085b9eb6b92f---tirujizoxunijarop.pdfIn PDF document text
    • http://sghscsjamarai.org/guruhargobind/userfiles/file/mosusoxixibepur.pdfIn PDF document text
    • https://adikkedua.com/contents//files/tolabigejujivajevubuwujot.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1607aefce2a632---vaxuluk.pdfIn PDF document text
    • https://www.litesourcenc.com/wp-content/plugins/super-forms/uploads/php/files/f03c231a62f9d553b40c51cb87cfe05a/bigetifizurilewokuxup.pdfIn PDF document text
    • http://big-blue-bus.com/pics/fotos/1/file/26373234555.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae8d272086---12576316577.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/695365779bbd32e65b11a05fef7e7c04/guxalexedut.pdfIn PDF document text
    • https://e-uchebnici.com/img/file/luzijimovo.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/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=friends+season+1+online+with+subtitlesPDF 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_off0000eb88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB88 5152 bytes
SHA-256: ee642ca2950511cb1578be9b826dad9921306771c25d077a277be4975d6cf723
font_01_sfnt_off0000fd1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD1C 13036 bytes
SHA-256: e6ec6b1875ce2948923acf20f1a467af90222f6d01e4280a5b5f12fa149c3bdf