Malicious PDF — malware analysis report

Static analysis result for SHA-256 81afdc6568c2a3af…

MALICIOUS

PDF

77.3 KB Created: 2021-05-28 05:07:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: b6e598b4562628c76fb7cc71a7a48a74 SHA-1: 38413a9064f77743b6b008f206dc5b44fb2ef5fe SHA-256: 81afdc6568c2a3af07e79dc65cd7efa8fe36d95658d082b4db20767c27a4b072
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

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://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/da4f55df1763214c797b30a6dcc31898/riridefizipeli.pdf In PDF document text
    • https://wulf-sanitaer.de/wp-content/plugins/super-forms/uploads/php/files/1jl7dttn6ejtm96j5is3ut50ld/nabixejazulukex.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/11536831694.pdfIn PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160722ab7e2276---86937653993.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/tifenodukujixumovagiva.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608199e3960c7---wogojubagu.pdfIn PDF document text
    • https://triptoboloyfoundation.org/editorsfiles/files/nomowurosofuwa.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16087ef9c2355f---68998019168.pdfIn PDF document text
    • http://dgjinhak.kr/DATA/upload/files/202105261043292897.pdfIn PDF document text
    • https://aduanaldelvalle.com/userfiles/file/84431903318.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609f48f8d2861---gojanalebolevilukoduvi.pdfIn PDF document text
    • https://cleaner.pl/userfiles/file/xiruwanapimupo.pdfIn PDF document text
    • http://all-pass.com/folder/editor/file/sepelitonifosowavevovojad.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/16098542f8147b---78272697836.pdfIn PDF document text
    • http://loveperfectionschool.com/upload/file/75534106768.pdfIn PDF document text
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/fd0e3e0a434c406c8e73b5a5525385cc/5695036418.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/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=la+odisea+resumen+completoPDF 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_off0000f08f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF08F 5160 bytes
SHA-256: 8db5fdfba5b9cae093d06895bbff0e8a9a6c5a25d1c93f2bd8332529728e15ef
font_01_sfnt_off0001020a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1020A 11392 bytes
SHA-256: b2bb8595b041162bf4a452079e1cc627257ebf8010dfa72a0e28894b342a2ef7