Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdc9f67979f5f46a…

MALICIOUS

PDF

85.9 KB Created: 2021-03-28 16:53:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: a6850cf9e85ba0d510dfa4a29c7c0f58 SHA-1: be3071d3585e912d3c134fe6aebb87f280de12b9 SHA-256: fdc9f67979f5f46a9bee9dd7fca74c778cfc2d024e721dc65ed2ce9dec5afdad
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://crophysi.ru/strik?utm_term=free+cookbook+maker+software PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4365570/normal_5fefdda42da20.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421061/normal_5fd14a26d9563.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464077/normal_60417dc6abe0a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4372702/normal_5ffbeff9c0217.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418781/normal_6006adbdc5fa4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/75973afd-7772-4941-b3f2-fc0f8e4b77f1/sex_offender_registry.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ab69fca9-7c4d-40b4-9484-15d1e51285ef/what_is_the_difference_between_paleo_and_mediterranean_diet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e7246b1e-dd21-4926-9157-6583dbc117ce/39832860439.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eece0d2a-3039-4c44-9e9c-3e1d88fc0563/84389345884.pdfIn PDF document text
    • https://a4758657-6aaa-4003-b0f6-1957e800abfd.filesusr.com/ugd/70c1f8_fef83148a3484f2098b34c22f0a0964d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/7a12c23f-ba25-436a-bea4-dabec5617f6b/xabesorunamik.pdfIn PDF document text
    • https://s3.amazonaws.com/piwanisaj/avg_antivirus_update_file_free.pdfIn PDF document text
    • https://c145ee04-3c3b-4786-8b94-e0511401b322.filesusr.com/ugd/de65f7_dde2af2c584645599a84a725dc479171.pdf?index=trueIn PDF document text
    • https://79d8ee67-2172-45f8-9737-086b37aa5bdf.filesusr.com/ugd/2ab2ae_3e5796176aec4819bbe7df9adda134fd.pdf?index=trueIn PDF document text
    • https://921790ca-7b53-43bd-a25d-275d6f056404.filesusr.com/ugd/9d24cb_250e091f541a4203a7c830b2fbdf5a7c.pdf?index=trueIn PDF document text
    • https://8a83ad47-1dc6-4e38-b726-138de0fe4a7e.filesusr.com/ugd/043c68_f150bc9c867a4403b47d4f8d830f71bd.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/fibesezati/91143776693.pdfIn PDF document text
    • https://8eccd3b7-fb20-4588-a5b5-4d8c58591879.filesusr.com/ugd/0e6328_2b20df431a9d4b529c41852b02c7dd71.pdf?index=trueIn PDF document text
    • https://c63359c4-faa5-40af-ad11-254ddd3d100c.filesusr.com/ugd/838c33_4946578b15dd4cfdbc1818b217de21f4.pdf?index=trueIn PDF document text
    • https://5be7aec3-7d66-433b-ae1d-2bfb807ddf2a.filesusr.com/ugd/24deb6_d324c08b25ec436e85d1f4d3b582b240.pdf?index=trueIn 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_off000110fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110FE 5244 bytes
SHA-256: 993451ae35844b6b26e71117fa054e7f57b4ce539191ff06709b38447f34137d
font_01_sfnt_off000122d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122D6 11916 bytes
SHA-256: 433621ec783f8a11adcf397c26a0e906d0cff9c7bf1b69a264657fac2f95c206