Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f36a2dab7aceba7…

MALICIOUS

PDF

81.6 KB Created: 2021-05-16 13:22:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: a63d0f3e9cf9b061aaecaeea32fac2a9 SHA-1: b1844715064f3d0c18a6a4f4ade83c63120ec7a5 SHA-256: 8f36a2dab7aceba7bf6e0f7346dc61089aea3866be8fed59fb3685dd64610dbc
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://resalured.ru/strik?utm_term=las+cajas+de+carton+libro+en+ingles PDF link annotation
    • https://cdn.sqhk.co/vinogusi/jhhitig/texorodoti.pdfIn PDF document text
    • https://cdn.sqhk.co/vavewiminiv/2HrX0EY/bowl._com_member_login.pdfIn PDF document text
    • http://bratskpravojur.ru/what_does_the_endocrine_system_control7oajm.pdfIn PDF document text
    • https://guwusupokase.weebly.com/uploads/1/3/1/4/131437041/welavukuzubifu.pdfIn PDF document text
    • https://rosanibo.weebly.com/uploads/1/3/4/8/134873488/vojaf.pdfIn PDF document text
    • https://tufuziboserivu.weebly.com/uploads/1/3/1/6/131636644/puzumerigidesu.pdfIn PDF document text
    • http://homebig.space/jdk_8_download_for_windows_2016_64_bitb2pjc.pdfIn PDF document text
    • http://blablablacar.online/kegevalrdu8k.pdfIn PDF document text
    • https://pukapukipek.weebly.com/uploads/1/3/4/6/134636258/juwajomaj-bizop-xugixobav-rofitavejavavif.pdfIn PDF document text
    • http://feelslike35.com/distribucion_hipergeometrica_ejercicpc6iv.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://e4c06157-4c4c-4c30-848d-1ce07482e123.filesusr.com/ugd/99e070_59304bb2002b4954b02f48d9a1f00339.pdf?index=trueIn PDF document text
    • https://951e66c5-660f-4748-bfcc-a6cc0831133d.filesusr.com/ugd/4967bb_fe444d1db105427396ebbda3fc5a3931.pdf?index=trueIn PDF document text
    • https://7043ee2c-bc2d-4d46-b82c-b0075177c1aa.filesusr.com/ugd/f862b5_b72ddb2747a143769e794ca9e098d71f.pdf?index=trueIn PDF document text
    • https://6f84c080-6bd2-4154-8ce1-0e390380bda5.filesusr.com/ugd/defdb4_6d4ef6febf604512a05ec5163dbaecac.pdf?index=trueIn PDF document text
    • https://ecf8b3bd-8201-449f-a39c-156acd88681e.filesusr.com/ugd/97634b_13330b923fac4e55a44432ca95f3a0a2.pdf?index=trueIn PDF document text
    • https://c7bff75e-0a19-4817-9d47-fca4cf08161b.filesusr.com/ugd/3b6424_61af5bcf21ea442e8cfbbd03ca8236e1.pdf?index=trueIn PDF document text
    • https://beca70af-11ea-46d2-a649-d7fd44c468ee.filesusr.com/ugd/dd41e2_206fc207a2ff4853bf0b477855c59ff0.pdf?index=trueIn PDF document text
    • https://7e574f8b-ef34-4833-8dee-b18f3ac9fc91.filesusr.com/ugd/af8ffd_e438a9ddba9640bcaba9dcb77c1e8283.pdf?index=trueIn PDF document text
    • https://86b7bb9a-6a0b-496c-a062-e8aa60c365d0.filesusr.com/ugd/dcf311_27c5737cccc64df2af431a1de41e0d99.pdf?index=trueIn PDF document text
    • https://836291d8-7b77-40db-be8c-3105928c7ef3.filesusr.com/ugd/aae074_efe5c54c081f49c28824542cde24f01c.pdf?index=trueIn PDF document text
    • https://790985df-dfec-4a08-b509-00f37668cf87.filesusr.com/ugd/a421e3_949afb8f11d64020bb344624dfb82fe5.pdf?index=trueIn 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e52e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE52E 5264 bytes
SHA-256: f07349f4ee09d6b16fd29595302e9c90dac6c35ac404266012c3b0a3d35a65d0
font_01_sfnt_off0000f723.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF723 12276 bytes
SHA-256: cd9e93a6724e94d7a55accf884ef83088de3c03e3ed9c25557cab86db7aa0f60
font_02_sfnt_off00011eaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EAA 16944 bytes
SHA-256: e8568f80d93bf8c58cde54958931787e350f72c83beb23e7cae2dece4aa5a3aa