Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cacf2f38ef38efe…

MALICIOUS

PDF

74.4 KB Created: 2021-06-10 19:59:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 5e46bb68d0062cb4e9a9c790f624277e SHA-1: 62a7f18971ce5e5a726377671b9e2dc48f6fa67e SHA-256: 4cacf2f38ef38efed7e6c5fe4b0d2afca31d0b40199c4ce44fce6c84b774cb31
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by both a machine learning classifier and ClamAV. It contains numerous external URIs and links to compromised CMS uploads, suggesting it is part of a link farm designed to redirect users to malicious sites. The document body, though heavily obfuscated, contains 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://pistant.ru/uplcv?utm_term=assault+air+bike+manual PDF link annotation
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/de55ee0b86238549b464483ac59a7e0b/jiwivokisefima.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/bubejeke.pdfIn PDF document text
    • https://bloomland.com/sites/bloomland.com/files/kuravagebom.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a23ab9b7257---95573622915.pdfIn PDF document text
    • https://almondzwealth.com/administrator/imagetemp/file/wifaravasax.pdfIn PDF document text
    • https://www.federatedlighting.com/wp-content/plugins/super-forms/uploads/php/files/725474fed181c647d799fe26876a2cbf/kenijizafu.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1608396838d69a---38784098677.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160ac9f76dbf88---kilikebipitepinotonevejul.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4083d7b875---73965450770.pdfIn PDF document text
    • https://kop-trans.pl/uploads/userfiles/files/totibe.pdfIn PDF document text
    • https://burstallconrad.com/editor_files/file/69531939573.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/fn0ru2k3altiuqerghak19vo92/26492130400.pdfIn PDF document text
    • https://www.perfumista.co.uk/wp-content/plugins/super-forms/uploads/php/files/97c4d866423587ac216c59c6d5e99dda/5291400748.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607eaf3a6ed57---71626794172.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/68dbc2e7e27108f6bccf332ade52eb69/kaniwewemakimurom.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/5b9aafbbeabca48cea8e451e8a6f365c/90043238024.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_off0000e7d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7D5 5024 bytes
SHA-256: f16b6b6830c7c65ec4a06a9b961ff188a64757ac3a170fcd214056791581e933
font_01_sfnt_off0000f8cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8CF 10496 bytes
SHA-256: e3af94bb59c3214501b409af048104233e04080a13350216b0ef6ede24d67b23