Malicious PDF — malware analysis report

Static analysis result for SHA-256 f88d567a24bd91a2…

MALICIOUS

PDF

73.7 KB Created: 2021-05-31 02:59:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: aa1cd0a47292796f72c293894a431218 SHA-1: c9152e17a5f9d632b601e3ff3cb912287fd45bdb SHA-256: f88d567a24bd91a2b0037657be279e10a4a0240442a4d1b53fb3a45bb2c544fc
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous links to compromised WordPress sites, suggesting it's part of a link farm designed to redirect users to malicious content or phishing pages. The presence of embedded URLs and the nature of the heuristics point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096b232a7fdf---wabujenurivimubikadifut.pdf In PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e75fddf632---65125048444.pdfIn PDF document text
    • http://www.odnpoznan.pl/fotki/file/file/94146938417.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/ovnqot7t8tqhlta2s9n33j2tk6/99274688614.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086c9156d21c---65173240060.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/migdb8mnqu5li6gfq4logjdb3d/vavesuwadabila.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/103c57fe2141c937a27385f2136db96b/891336878.pdfIn PDF document text
    • https://amerismithenterprises.com/wp-content/plugins/super-forms/uploads/php/files/7bded93a1569b04905a51be04a42541b/mobesuvafegiminemoreda.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087e23129f75---28972960663.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/1516bb2d64ebfc1613049d7dbad97f60/xamakox.pdfIn PDF document text
    • https://lacecinella.com/writable/public/userfiles/file/nimigugi.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16094649d67578---wixajagiregudutexomeme.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/59294b5b949a121c1efad62a773e244d/pukipag.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4e5f5fbfe---vuvawuguvufexivejeka.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/ogda21eni82g3k0c35midhg2kj/48047434905.pdfIn PDF document text
    • http://www.melloecastro.com/wp-content/plugins/formcraft/file-upload/server/content/files/160889d91c4e6e---molokekilubekoludibobim.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/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+relax+stressed+dogPDF 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_off0000e502.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE502 5116 bytes
SHA-256: 8b296a77a1aa05250d2b4f62dc34ce6e44c25a5986096087478852733b654d1a
font_01_sfnt_off0000f681.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF681 10280 bytes
SHA-256: 5e49aa3a6ec16ed9b3b090de9bb1741fef769c6dafdad3f3577cdc73d3599d71