Malicious PDF — malware analysis report

Static analysis result for SHA-256 61343cde0d75b381…

MALICIOUS

PDF

76.0 KB Created: 2021-05-11 20:04:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: f6a8870d843bc61da13b6aff0fafbaf4 SHA-1: 7163e1c4192d6fd8a7bcc49356f8ee1ba675083a SHA-256: 61343cde0d75b381e604ff5d4a1c1a62a07121fe4ce1a3fe71cb63ae864a7c20
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable hosting, indicating a link farm or SEO spamming operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded URLs and the nature of the link farm suggest an attempt to drive traffic to malicious sites.

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://botokaw.ru/strik?utm_term=grammaire+fran%25C3%25A7aise+niveau+universitaire+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4416143/normal_605a1f88e3b98.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414680/normal_6057b102439d4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419211/normal_602e6a1ace048.pdfIn PDF document text
    • https://togawakavepanef.weebly.com/uploads/1/3/1/1/131163752/3326251.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426425/normal_6011231a6e59d.pdfIn PDF document text
    • https://vepemetamat.weebly.com/uploads/1/3/4/3/134354227/3811652.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444353/normal_600bb056717df.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450625/normal_6062e6a0b42fe.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://5cbbff6b-7c47-4fbb-abda-9de5069fbc88.filesusr.com/ugd/1a89c8_70841d5e91034d8fa787c8eb21ad8899.pdf?index=trueIn PDF document text
    • http://sidinikoxa.epizy.com/corel_draw_x7_serial_number_and_activation_code.pdfIn PDF document text
    • https://3745348a-78a0-42d7-8ff4-af2b45bf5faf.filesusr.com/ugd/02631b_8eef66e253054c16991779da5f283f7a.pdf?index=trueIn PDF document text
    • https://34570882-574e-4d25-8c0e-d8b9b6c2967f.filesusr.com/ugd/cb2bed_3352f86ee3a54bd6838f1d3a77c316ca.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e84a8b5c-9f82-41c1-b901-ee8e0d796c0b/2230718035.pdfIn PDF document text
    • http://juvusamis.epizy.com/ir_functional_group_region.pdfIn PDF document text
    • http://mazizinopuki.rf.gd/how_to_restart_your_furnace_when_you_run_out_of_oil.pdfIn PDF document text
    • https://94e55d9a-ad7c-4b6b-a54a-a00202ad3087.filesusr.com/ugd/208fd7_1e5d3673d75e4933b4eede321041d376.pdf?index=trueIn PDF document text
    • https://63d876aa-455f-4c41-9c38-50747f3e0b95.filesusr.com/ugd/a220d5_53a9baab67004c8ab773861d45f0d9af.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1d120710-9d1d-4f97-8305-d08dd8cdaedb/95657221678.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/17221f92-fc41-4e21-a709-67444046de64/xojumivebuxidajuzefim.pdfIn 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_off0000e582.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE582 5428 bytes
SHA-256: 0a9e163c684982e3c458b1cfd4211a1b36e1e3d30bcc0979d79d4ed464f64e58
font_01_sfnt_off0000f7f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F3 12516 bytes
SHA-256: cee6e30cd5a41754caddf9d8c83e28e54021afc57205a12d605a1c3f03d52894