Malicious PDF — malware analysis report

Static analysis result for SHA-256 03989255f3fa67ef…

MALICIOUS

PDF

80.6 KB Created: 2021-04-05 13:00:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 082156d561f6c687d0bac002daa390f4 SHA-1: b302e9a54f5e4ad168fad3eb1e644b62f9048ea0 SHA-256: 03989255f3fa67ef6fbfd449fb0624f95dc360def47bcf906004571290e15520
126 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to disposable hosting and are flagged as part of a link farm. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as Pdf.Phishing.Trojan. The document body, though heavily obfuscated, appears to be a lure related to 'human resources administration', aiming to trick users into clicking malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • 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 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/award?keyword=administracion+de+recursos+humanos+libro+pdf PDF link annotation
    • http://tuderoba.getenjoyment.net/letra_del_himno_nacional_mexicano_escolar.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4464077/normal_5fdd9ef4000e9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419451/normal_604027b1ca528.pdfIn PDF document text
    • http://pifofobexaxel.mypressonline.com/forms_and_functions_of_nouns.pdfIn PDF document text
    • http://discout.online/best_picture_settings_for_samsung_tv_for_gaminghr4dz.pdfIn PDF document text
    • http://rewita.fun/capitu_e_bentinhomdry7.pdfIn PDF document text
    • http://naturfresh.fun/la_fiesta_de_las_salchichas_espaol_latinonnk3w.pdfIn PDF document text
    • http://tradestaroffice.com/51899173654qgdqj.pdfIn PDF document text
    • http://skidki-day.site/67788567068qs2ko.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469375/normal_602b62d6ab434.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466676/normal_60242c8352985.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368964/normal_5fdda05430c58.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://69a21580-3c80-4f81-8097-1ec0bc18215d.filesusr.com/ugd/bd7df1_9dc232e28cd5407e964e4db781667dd5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e8842ae-1012-498a-8c6c-6d607e256275/savage_worlds_rules_cheat_sheet.pdfIn PDF document text
    • https://ee60c613-3dd1-430d-b711-08e3dcbf0273.filesusr.com/ugd/19ce5d_3e18a9ad8faa4ff49bc4e74c929c91a9.pdf?index=trueIn PDF document text
    • https://28a90398-13b1-4b58-b54c-ed045a6bddf2.filesusr.com/ugd/7e9e1f_34cecd72fe2443d69791721b3b62001e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a325f33c-73f5-4d9e-b6a2-d24589e0e735/rene_guenon_king_of_the_world.pdfIn PDF document text
    • https://aaf2f8d8-4593-4070-95c3-ed2308805076.filesusr.com/ugd/337eea_51593a48212d4d45895f81c895f2da0c.pdf?index=trueIn PDF document text
    • https://ac4cd5cf-e861-4b1b-a585-e47049f737a6.filesusr.com/ugd/843280_96948a89e854466fa2c5a32649288948.pdf?index=trueIn PDF document text
    • https://80172413-d145-4b71-b7cf-4a007d76ad29.filesusr.com/ugd/cacfd7_1c46a00bd5404161bbdb00b390b0a462.pdf?index=trueIn PDF document text
    • https://d89a15f7-21b5-45f0-b9b4-bc5b7be68842.filesusr.com/ugd/18e821_d8b096ffe27944688c01e20a3f0ada2f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0f05481e-f552-4ccf-a1f1-db7f8f6c8a18/42742743123.pdfIn PDF document text
    • https://45dcde1a-aed5-4138-b95e-a0f768a283bf.filesusr.com/ugd/89441e_681be08dcfc34ddc8b1e9a607bd5269b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/700de1eb-9da4-4185-9be8-01daeedc8d99/18922711901.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f342582f-d340-4a02-bbb1-41186d2de95b/kegiwi.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_off0000f7a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A1 5524 bytes
SHA-256: a06167f088da90bd526916068edd612d1bdf0687a043af452f4c3189e4883fef
font_01_sfnt_off00010a39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A39 12340 bytes
SHA-256: b635f3053eba6b6f920d5f1378458698d078a0b5257af3c2fdcdada4a0e64f4e