Malicious PDF — malware analysis report

Static analysis result for SHA-256 473da6752ef04721…

MALICIOUS

PDF

77.3 KB Created: 2021-03-24 10:12:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: a15088e37e74cd4e8817abb2e5038f3e SHA-1: b16bc2571620824088c973e780f9da88afa634e0 SHA-256: 473da6752ef047214fc5b99a320f47fc58600426f7b971f52a7a52005b098edd
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable hosting and employing UTM parameters, indicative of a link farm designed to redirect users to malicious sites. Heuristics like PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM strongly suggest this phishing or malware distribution intent. The ML classifier and ClamAV detection further support the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://lozipotod.ru/strik?utm_term=mcgraw+hill+connect+student+login PDF link annotation
    • https://kujunegisim.weebly.com/uploads/1/3/1/3/131380440/b216b.pdfIn PDF document text
    • https://vumorusumanipav.weebly.com/uploads/1/3/4/2/134234742/978741.pdfIn PDF document text
    • http://raisinshq.club/3791510811y49jt.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456705/normal_605422fed3f6f.pdfIn PDF document text
    • https://xijegubusogo.weebly.com/uploads/1/3/0/7/130739006/97479.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403262/normal_600278d90aece.pdfIn PDF document text
    • https://zefopezonokav.weebly.com/uploads/1/3/1/3/131398054/nimak_gagur_vivurumojani_tejizefodad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457838/normal_6022a2c47fada.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485699/normal_603f53ce3d5f5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409818/normal_60289f632a297.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393762/normal_5feeaee342a04.pdfIn PDF document text
    • http://leadtop.co/32183083984oyukd.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4445544/normal_5ff2e658c58bf.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4378160/normal_60018e3255b42.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://42172c5f-463d-425f-bc49-3536d5e9b788.filesusr.com/ugd/3e9aab_f6dd2160922c4b458ea2d7a37180b777.pdf?index=trueIn PDF document text
    • https://e4034479-4ead-418b-af8c-5be8dc72bdbe.filesusr.com/ugd/1e8759_01aa4c1ae1f041bba1c6004ce8bdd382.pdf?index=trueIn PDF document text
    • https://12f7643e-9106-4823-89c2-0bdaecd1bc22.filesusr.com/ugd/1f6d71_38190049f8424ff7b1f10968ed7192d9.pdf?index=trueIn PDF document text
    • https://2b075577-062e-477b-ba44-a680027dca12.filesusr.com/ugd/ee943f_c10a648cce584d6589c5b73b90031418.pdf?index=trueIn PDF document text
    • https://f4b9ed98-44c1-44e6-9966-d9817cd43de7.filesusr.com/ugd/9ced5d_1074a323453b46d69358de566fcb94bd.pdf?index=trueIn PDF document text
    • https://4f0f5a39-0a2f-4cdf-b4e4-40a644fad8b9.filesusr.com/ugd/2024fe_d1f2b68cc5bd40b8aad32906b65e2f2b.pdf?index=trueIn PDF document text
    • https://46c0acaa-de7d-4f46-84f0-c2cf1d8ff7d9.filesusr.com/ugd/ac1638_e837b687ba9c40aeb490bbae010bc61d.pdf?index=trueIn PDF document text
    • https://f238abdf-92e3-4651-90df-65b6e8a648d9.filesusr.com/ugd/99965f_023354ca3572404ebf35f72b3e943c29.pdf?index=trueIn PDF document text
    • https://1261df91-4e32-40b2-8b8a-4050d3c54cbb.filesusr.com/ugd/df69c1_8e2b487bd7624e208237a997cea5633e.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_off0000edc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDC6 5296 bytes
SHA-256: 5cffcd162a1ad2be8e0ff128bdf2f1326c84ebb8c12809b7eca243be7e0a08d1
font_01_sfnt_off0000ffdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFDF 11644 bytes
SHA-256: a32889c26c7ada7d1d50d8458a856fb225f48e317c367e802f916d80f3b84150