Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c3a6bf930cc5dd3…

MALICIOUS

PDF

81.4 KB Created: 2021-05-02 15:45:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: 4c067421dd428bf276af45a4d179dd82 SHA-1: 88bfb55476f35312e65f3da8a2a4e8541a78b976 SHA-256: 8c3a6bf930cc5dd32a79a19af7fa00b128fb53753ca7096c8ff393825f25bb64
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable domains, and is flagged by ML classifiers and ClamAV as malicious. The presence of external URIs and link farm heuristics suggests an attempt to redirect users to malicious content. Although no scripts were explicitly extracted, the PDF structure and embedded URLs indicate a phishing or malware distribution attempt, likely using a spearphishing attachment vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 5

  • 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 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://mezovuduw.ru/strik?utm_term=attachment+style+questionnaire+for+adults+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4412159/normal_6054bd76c689e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420250/normal_603115632f5fb.pdfIn PDF document text
    • http://liropade.22web.org/equivalent_fractions_worksheets_year_2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4401703/normal_6046000347a00.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489724/normal_60385afd88b57.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366371/normal_600235d6f399e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451220/normal_6065d268b48d0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425484/normal_5ff686a0d1c2d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414494/normal_6019b16c756a6.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vesofimuni.rf.gd/carlyle_annual_report_2020.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c562cf9e-0f11-4f2d-9dfe-e42eb37c9369/61980672391.pdfIn PDF document text
    • http://vedumojaje.epizy.com/mit_app_inventor_2.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3b42fa94-ed4f-404f-a99f-7e4de4ec9a5f/xobasegunonuxejirozibodib.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a284dec7-9494-40f3-8b0e-f13030568c5a/how_many_calories_in_a_medium_iced_coffee_from_dunkin_donuts.pdfIn PDF document text
    • http://nopuwezivobevuk.rf.gd/47968557874.pdfIn PDF document text
    • http://ralorepozariti.rf.gd/definition_of_e_marketing.pdfIn PDF document text
    • http://kobelitorapojop.rf.gd/how_to_operate_a_singer_heavy_duty_sewing_machine.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2552ad4e-a19c-4121-ad4c-87ee7c704e55/nuradupusosazexotivud.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ae72ffea-7e86-4ab7-a449-cbb4f1b6b1e4/qsc_rmx_1450_for_sale.pdfIn PDF document text
    • http://vubedarav.epizy.com/lopejuwobuliferisuposimo.pdfIn PDF document text
    • http://zuribetemeriguk.epizy.com/what_can_you_do_with_a_degree_in_data_science.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ed7dd56-122f-4ea6-b46b-0dfcf55bd033/mcgraw-hill_my_math_grade_5_teacher_edition_volume_1.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3709a7b2-56f1-45ba-be99-668908c03d33/24112089876.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_off0000fe93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE93 5612 bytes
SHA-256: 3300df6817d7c147eba4c86a123ecaf286898a16902e635483f6bec5e4815455
font_01_sfnt_off00011186.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11186 11048 bytes
SHA-256: 106959334cd9c119eb4cc2164200994af512fb06c0a89ca239fc1f15ce1554b8