Malicious PDF — malware analysis report

Static analysis result for SHA-256 528cf94cf7f72abb…

MALICIOUS

PDF

74.4 KB Created: 2021-05-20 06:20:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: 05029c39452b95307a0ea031ede73f72 SHA-1: 6dbe64b5fd1aaea24642d6e2483c0077722e35ff SHA-256: 528cf94cf7f72abb1d13416cfdb053b99f43c9e9233cd074ff9b6c3b2960ec81
156 Risk Score

Malware Insights

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

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to compromised websites, indicating a link farm designed to redirect users to malicious content. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, suggesting the document's primary purpose is to host these redirect links.

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 http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070ffef9e26a---gofapivopudesa.pdf In PDF document text
    • https://artenika.pl/fck/file/88488219721.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/bikivuxedil.pdfIn PDF document text
    • http://arch-teh.com/pic/userfile/lipisujisod.pdfIn PDF document text
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/juvqnulgs0jc566knasf8fr521/36638832487.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/f67e349f1b33dea898ecea7814b6d15c/kafakamurigu.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/uaemtlsi991om106tno8n363d2/bozuzidumijawutibeva.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2fb41f140---47116229900.pdfIn PDF document text
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160784e9e61226---vavelobexarisilu.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/zubig.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086e29b325d9---fitozujovinal.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16090b1bb75c12---77185673930.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160837c88c88c5---waburusatidol.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160721c4b68642---51484781424.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=global+problems+and+the+culture+of+capitalism+free+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d833.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD833 5448 bytes
SHA-256: ff5d26aa138d142c98f0a5401fa2e286660830f522c1b981b0a041677ec38d4c
font_01_sfnt_off0000ea81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA81 10416 bytes
SHA-256: 349e2a3e00e0ce557f593571f4edc5524e9bb042ebd7d79b0457cea9b8d8d42f
font_02_sfnt_off00010e05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E05 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333