Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd43c7a501002b84…

MALICIOUS

PDF

78.2 KB Created: 2021-06-15 20:28:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-17
MD5: d2f8e050dd776837a377ffd59efd9d8f SHA-1: b5b6637993c4f890dd76fa728b956e319f7eaf40 SHA-256: cd43c7a501002b84a7336543cb0a40cfe4e2ba5b961d627848b34545e3a22ec8
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains numerous external URIs and points to compromised CMS upload storage, suggesting it functions as a link farm to distribute malicious content or phish users. The presence of multiple distinct hosts and the use of 'utm_term' parameters further support the interpretation of a link farm designed for SEO manipulation or malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://huntic.ru/uplcv?utm_term=jokes+about+pickles PDF link annotation
    • http://files.ibiza-ferien.de/file/kakokobujawusetigabelapi.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/ebd25102b5a7d18978deb2d2780701a6/28596088928.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1e0fdd78f3---dazidujivi.pdfIn PDF document text
    • http://geologicatoscana.eu/userfiles/files/40550167945.pdfIn PDF document text
    • https://heritagecambodiatravel.com/userfiles/file/92143944156.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/4bgl58g0rtd7io1ebspvos848c/reditoladoso.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bfbb86ce3ac---kowezamo.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1ebc6763a9---vemokezagofakiru.pdfIn PDF document text
    • http://alphaconsultinggroup.us/vpw/images/file/dovitajoxu.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/160991cd865586---romibilapujowinadum.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/1pphbh46629uappjpj214mpa4b/20822531628.pdfIn PDF document text
    • http://espacioschillout.es/images/admin/file/xidojazoduligabofab.pdfIn PDF document text
    • http://xn--l3cbpp3gh4a5g5c.com/userfiles/files/89879442895.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087fa1044e21---zujiwonasafukepa.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a972141b3d3---86362092651.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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_off0000f43f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF43F 5024 bytes
SHA-256: a6e844b26c51dec5afb4197e8523049715e52e889d408f9a6974311862c278cd
font_01_sfnt_off00010569.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10569 11004 bytes
SHA-256: 1036f59153da7f798fa0c7943be03be5e852a162f9a34267c038325f191d1d73