Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c87145366865ac7…

MALICIOUS

PDF

79.1 KB Created: 2021-06-12 23:57:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 8ae648f76d003f55ae4c5a13992a9b62 SHA-1: 685c3a8c06d3dcbf996fa04eaa0372be33cb3902 SHA-256: 2c87145366865ac7677aeb9d50de99b4bf61f51d6f0ef1a2fbc71f9befc16f7a
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-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://inwebjor.ru/pbw?utm_term=toefl+essay+writing+topics+with+answers+pdf PDF link annotation
    • https://wazumiwu.weebly.com/uploads/1/3/6/0/136038811/f2c54.pdfIn PDF document text
    • https://mukuriwubi.weebly.com/uploads/1/3/1/4/131483253/9929752.pdfIn PDF document text
    • https://nixabuvibowigev.weebly.com/uploads/1/3/4/3/134308208/52acd7.pdfIn PDF document text
    • https://kixuvatapowow.weebly.com/uploads/1/3/1/3/131383305/xatisuzeba_vebudonuz_wekelaxivuru_titelomajap.pdfIn PDF document text
    • https://kepudeveru.weebly.com/uploads/1/3/4/6/134698703/femitifefima.pdfIn PDF document text
    • https://dawujorukola.weebly.com/uploads/1/3/4/6/134683436/ralisufefodo_refumalidoxaso_kelulu_togorebidaruked.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501791/normal_6027c1b160aa0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422133/normal_5fdaf7d617fc9.pdfIn PDF document text
    • https://wajogivetiwi.weebly.com/uploads/1/3/4/3/134322864/dulid.pdfIn PDF document text
    • https://jozudepixivi.weebly.com/uploads/1/3/4/6/134682498/zefoxulabexuxa.pdfIn PDF document text
    • https://lonupuvajofova.weebly.com/uploads/1/3/4/3/134341927/c05d2.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://kosubufegu.pbworks.com/f/download_anime_sword_art_online_alicization.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e1f280c3-165b-4759-9f91-c7f990c7388a/student_loan_payoff_excel_spreadsheet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8bea882d-bab3-4782-911f-ab7a7f2aa2e8/database_system_security_policy.pdfIn PDF document text
    • http://kosumepifise.pbworks.com/f/efootball_pes_20_ppsspp_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f4916660-bdbd-4791-97ca-898ff20f017f/medical_spanish_app.pdfIn PDF document text
    • http://fepewuwakow.pbworks.com/w/file/fetch/144720966/goredatixedewipevowul.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ad2556e9-9aaf-4e85-b9af-10207a24436f/70473493098.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/54496dd5-1602-4ac7-b877-d8ed95983ad2/parts_of_speech_worksheet_for_class_8_cbse.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6e2d36b8-daf0-4d90-9d4d-026a1d0cc2d1/xajubokajefedutitadonarot.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_off0000f6b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6B4 5560 bytes
SHA-256: 5d192f18af9c89292aa0860686ece9a76a495c0e49c90c2ade036a0b65690af6
font_01_sfnt_off000109b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109B4 10916 bytes
SHA-256: 112148b20cbb2e0af24198603433d2075d90a817fba23344d3c33c7d0ccf4fd5