Malicious PDF — malware analysis report

Static analysis result for SHA-256 31d67b35d54cfd3b…

MALICIOUS

PDF

69.7 KB Created: 2021-06-06 06:34:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: ea9fbb7be573c2267abbc5e3db2682f7 SHA-1: be712bef02dd4f811f146dd066fdad4fa32dfadd SHA-256: 31d67b35d54cfd3be4c0e4f71b78b28daebf8c54660034a0f06dc5541655c841
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ML classifiers and ClamAV. It contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, appears to mimic search result snippets, likely as a lure to encourage clicks on the embedded malicious URLs.

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://medvor.ru/uplcv?utm_term=how+do+i+change+the+filter+in+my+cpap+machine PDF link annotation
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0d4dd2063c---87085296376.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada93c45121---kenesuxawar.pdfIn PDF document text
    • http://birzebbugastpetersfc.com/files/file/19160509120.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/6elrehavdc3kpd3l8gkqk65lih/94786321829.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b5b8ade08de---nunijobok.pdfIn PDF document text
    • http://dambi.pl/userfiles/file/zafarazomikatinazalexosoj.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/160b69d3403d18---22071104568.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/e296cf71eda4a75ca07d8f0d320d2e42/renonujamofepofemeva.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/598dd15f81bd7fedced1dee2a3c06dfa/40372354057.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/dceo56dq3nqslehjjn148moda5/3032970147.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/67e1dd5ba5bf687fbf32bf785a039df8/26868817162.pdfIn PDF document text
    • https://hogies.com/includes/template/uploads/file/lulesulukofiluxuk.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160708c1ce0e69---bularelavakigumutomed.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094d90dd1478---90036872536.pdfIn PDF document text
    • https://alice-immo.com/userfiles/file/limumaropudukivazed.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f62b96c495---78567049875.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_off0000d28e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD28E 5548 bytes
SHA-256: 9fe412f726f780c52534ed3a412894a72250e06e6756843f6ef7c411e1fe933f
font_01_sfnt_off0000e55e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE55E 10716 bytes
SHA-256: 9e5040dbc68c40d872571f5849b872fbbc6ed7a2c8457d8ab30afaab3dd395a6