Malicious PDF — malware analysis report

Static analysis result for SHA-256 c901635230ed85c8…

MALICIOUS

PDF

73.1 KB Created: 2021-05-15 16:02:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 0a9ec187af3b3ee2384a53d924df309a SHA-1: 02d943bff876dd693b605b35e4a97d637991727b SHA-256: c901635230ed85c87b4c7a5388e1dc70d3df77fde002e39e7ad665da642eb7b4
156 Risk Score

Malware Insights

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

This PDF document is classified as malicious by ML and ClamAV, indicating a high likelihood of threat. It functions as a link farm, directing users to compromised WordPress sites hosting further malicious PDFs, disguised as free software downloads. The presence of multiple external URIs and link farm heuristics strongly suggests a phishing or malware distribution attempt.

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://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608ddac02f192---limamimugutowizuvuberef.pdf In PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16078c2c24c8c5---49060343129.pdfIn PDF document text
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608f1bd99d120---ruxuzimuvizupupop.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/cde2496a79066e9c9979dcf08fd5ef0b/xuvuruzozolaponifanewenax.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/774a9f3d1a1f58933066b68d0e8b6ede/nomawijixol.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/a5emjad29njh32cs9fkrk6ippf/vodulepopiwuwu.pdfIn PDF document text
    • https://www.hemoroidklinigi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb3ef25941---57999397805.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/081b9bd945af3dbf7dd69b02a1dc45ac/88714758831.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16074a66db0c38---dusitosadafameponedufid.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/e41d13e93d221f6473294cb1f88cffea/gozobosasosewanabimona.pdfIn PDF document text
    • https://maspacientes.es/wp-content/plugins/super-forms/uploads/php/files/8vbpjn9c8p5tuct45f9fpe2b02/gusamon.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1608959e0a18eb---21000384656.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/2766a9b6093f53496ff7583c5386df2e/72366109134.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd9d494ac7---nopinizonofilepoti.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/12d66491c02e1543d76a93d16fe78f17/7450474823.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/cv9VXjIrmdE/uplcv?utm_term=free++audacity+software+for+windows+xpPDF 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_off0000e15c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE15C 5336 bytes
SHA-256: bc4de43d57d247eb1833c6d50010f48f233741cc0666016e1a0de8dc68438f04
font_01_sfnt_off0000f3b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B3 10480 bytes
SHA-256: a9a59e45c0c073c8d6d5106105e01fb120820cecdb7b4e0b64c2495deddbc5f4