Malicious PDF — malware analysis report

Static analysis result for SHA-256 b26753c1f45548d6…

MALICIOUS

PDF

77.0 KB Created: 2021-05-29 18:26:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 8b4b82b396ec6f967bc8e69ab755c49f SHA-1: 1241dbb6d0f60e83a52dd2768d9dae0044e08a48 SHA-256: b26753c1f45548d6e78d5393ecbd563e6ca0e17603dbb0d312a351a55ccd8877
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 0.9990

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://leonvi.ru/strik?utm_term=pop+slots+free+chips+2021 PDF link annotation
    • https://sikovoropis.weebly.com/uploads/1/3/4/4/134473700/3480807.pdfIn PDF document text
    • https://wivikomale.weebly.com/uploads/1/3/2/7/132740486/98b7885205ef04.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403681/normal_5fc843928dbeb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443574/normal_604f42ef9b1f6.pdfIn PDF document text
    • https://xujebope.weebly.com/uploads/1/3/4/0/134018561/befom.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4366957/normal_60b24d0c1b75c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4452846/normal_5ff80c352435e.pdfIn PDF document text
    • https://doxagazezuzizum.weebly.com/uploads/1/3/1/6/131606815/345ee89c86a7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4493553/normal_6046877304e64.pdfIn PDF document text
    • https://bofazereb.weebly.com/uploads/1/3/4/6/134675062/vuputatubu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408483/normal_601e76aae8bf2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489835/normal_60393ce91ddc8.pdfIn PDF document text
    • https://vusesuke.weebly.com/uploads/1/3/4/7/134723580/binogavodu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369793/normal_5fc747ebe37b1.pdfIn PDF document text
    • https://tevumusavobe.weebly.com/uploads/1/3/4/1/134108657/rodelivatiga.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4475215/normal_6001e49212229.pdfIn PDF document text
    • https://fojakejozu.weebly.com/uploads/1/3/2/7/132712415/revizuduk.pdfIn PDF document text
    • https://merasata.weebly.com/uploads/1/3/1/3/131378960/morexoga.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/9181673d-eaf3-4270-8a42-e7a4d9856981/us_postal_service_customs_form_apo_address.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c820351-2f87-4b8b-b59d-897593e3df42/dodufekaruxakuritatatud.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2b0c5585-37f6-4b89-9f81-40c54ecc78b3/reading_order_of_dork_diaries.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/877062d3-7817-4032-a22b-dda3a63ffaae/are_delta_shower_handles_interchangeable.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/505a96ef-0c10-404d-8d5d-1f1347a3c2b9/estudio_del_trabajo_1_materiales.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e18e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE18E 4900 bytes
SHA-256: eeb018319806c7894e724da98c2f721e20a74b94bfd53431c3686516d2af1acc
font_01_sfnt_off0000f24f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF24F 11172 bytes
SHA-256: fc51c19ddfefbe8b400915858862e8f42290a90aa02d82d4e8b4fa0839c3a6d3
font_02_sfnt_off0001181b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1181B 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34