Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff83b4bd2b4e06fa…

MALICIOUS

PDF

67.9 KB Created: 2021-05-28 16:55:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 2baeaaac0d91d97c49c2ae88846487ad SHA-1: 54722cd02a5de6598a74ffc381fdf16ca3ecac29 SHA-256: ff83b4bd2b4e06fa15bddff2da398c9f2c48010e987dabf9e00f1fec8833847a
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 0.9996

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://kuzutuzo.ru/strik?utm_term=assistir+a+novela+os+dez+mandamentos+cap+150 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4379384/normal_6011e8dd9ab9b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368951/normal_604885c2be47f.pdfIn PDF document text
    • https://mikugixu.weebly.com/uploads/1/3/1/4/131438693/1112883.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4475380/normal_5fcbfeb3ea24d.pdfIn PDF document text
    • https://nitelozam.weebly.com/uploads/1/3/5/3/135308565/siganevuwakipilure.pdfIn PDF document text
    • https://rusapaja.weebly.com/uploads/1/3/4/6/134617617/bixur.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384325/normal_6002830ddb2b6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425908/normal_5fe49ad4c1db8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415525/normal_5fdb8a4699231.pdfIn PDF document text
    • https://marezupudi.weebly.com/uploads/1/3/0/8/130874377/28b5552f328a7f.pdfIn PDF document text
    • https://suxasamivozafe.weebly.com/uploads/1/3/4/7/134705269/nusikokodexaren.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501963/normal_604f2a9f4ac63.pdfIn PDF document text
    • https://pejexiguwela.weebly.com/uploads/1/3/1/1/131164442/zamut.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484376/normal_606da54fead11.pdfIn PDF document text
    • https://dikefurilixi.weebly.com/uploads/1/3/4/6/134684794/batubet.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/dc5a073e-05d9-4bf3-b2fc-7f6afb6233c7/bubazozaginepinofapotug.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b1005fad-f1ef-4e3c-bbdf-dffa0b891c4e/ascii_values_binary.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cfd230e5-184c-4ed1-92cf-9afc2a856465/elite_platinum_7_qt_air_fryer_reviews.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ea44025-5903-4d9f-9d23-abd147520976/introduction_to_airborne_radar_stimson.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eb41c9d1-6fff-49c1-93ab-e73298fa9c34/critical_analysis_essay_grading_rubric.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/739b888a-0a6b-4dc1-9bab-4a5d3a52de10/porter_cable_6902_router_for_sale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/36235f9f-50d3-444d-8c09-b0c20b862eeb/what_is_chlorophyll_in_leaves.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_off0000ca4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA4D 5636 bytes
SHA-256: d6c170f3c6a21b166c30ed45b1d48a6605347769bcfe4818f7f09e2f70fe9500
font_01_sfnt_off0000dd7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD7B 11196 bytes
SHA-256: 6babed14eae58cbe3ab1d9fa705d03457a32cbd619ec148417b1e6f57b52b032