Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5357d8e71d4c5e0…

MALICIOUS

PDF

73.9 KB Created: 2021-06-19 12:26:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 2c26356486d8916a84d72667db1f26a3 SHA-1: d84033b638c563c4f488eea25e738562dd2de5fa SHA-256: f5357d8e71d4c5e061c9e640933e50ff21cba90f549d202f11a15e8db22e66f1
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm or phishing lure. The document body contains garbled text and metadata related to 'wkhtmltopdf', indicating it was likely generated programmatically to host these 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 https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/39601bb2d126722c0d8a33dbd5d170ba/lasix.pdf In PDF document text
    • https://ols.lighting/wp-content/plugins/super-forms/uploads/php/files/5abebf8f8ebcffe4a7b12fece5a7d01d/15023383368.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5c78d0c39---bejova.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/hlvpagfq4r0q9j1q795cfmfjs5/mekamejuxuvelaguve.pdfIn PDF document text
    • http://ferrogep99.hu/static/media/file/47617410708.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/6366ipesb9l93ehbq0hjisa43r/papawisosivuvevekelu.pdfIn PDF document text
    • https://grancom.by/upload/docs/45613666742.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0d5de6714---64035677990.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/750af3783827a04032a35196ab6d1dd7/74566032216.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e78e231e53---gunulafufalirotadivejar.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/gis2jhpb8r26f429ki7kg7m8mo/videfupidukawoxonizipulil.pdfIn PDF document text
    • http://caratow.nl/userfiles/file/setepuk.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/427f3bd06ac5625d2c2404b991e59c6f/55220759687.pdfIn PDF document text
    • https://ajitcoatings.com/uploads/xulonetijekemiro.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b3046579ea4---zudubarixazo.pdfIn PDF document text
    • http://andreaslasnik.com/data/files/viwubajakofezewewomubumow.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=boboiboy+full+movie+2+in+englishPDF 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_off0000e3ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3AE 5360 bytes
SHA-256: aff203ecd933c293672be6df23a404c4ca583944bac70510f6a02868748f940f
font_01_sfnt_off0000f5e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E4 10736 bytes
SHA-256: 9c886b4c7f5e6a5428bd99ac5174ba17e6c93a78ae5a838414164a4b87248edf