Malicious PDF — malware analysis report

Static analysis result for SHA-256 6bef7183083521d8…

MALICIOUS

PDF

70.7 KB Created: 2021-04-04 16:25:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 13f9572b5f932e9eaf11878675619080 SHA-1: 503657cdf588048a934dc3ca99b4c5b0763b7874 SHA-256: 6bef7183083521d83d3d4a3817949129bea220f707ea7967560fe8737dd7e15a
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 0.9992

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://seumenha.ru/123?utm_term=baraja+al+koran+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4383582/normal_605c72d7ac767.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479921/normal_603648f161ae0.pdfIn PDF document text
    • http://bewilotaweje.mywebcommunity.org/where_is_the_unloader_valve_on_a_karcher_pressure_washer.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4372963/normal_5fee4557d7fbf.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4476578/normal_5fcd8a7c9222f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387704/normal_6064550b36d60.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370303/normal_601f8fc293c84.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418590/normal_5fcaaedd7334e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460477/normal_604de6bbce570.pdfIn PDF document text
    • http://sosiwawivijomo.scienceontheweb.net/94368792929.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420237/normal_603486584bba7.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/410340ec-213d-4350-ae55-1e63c25f6f62/irregular_preterite_verbs_list_spanish.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c5fa91fa-5408-43d1-8f03-737714021c10/quadratic_equation_exercise_4.2_class_10.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/76b5b682-6f53-4b91-a789-f15adfcabca1/world_war_z_ps4_gameplay_fr.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/48695bf5-8108-4b5c-8ddf-ddd1f3ed61d0/36379885083.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/54346dde-3953-4087-8471-119a3915cdb7/orange_jumping_spider_california.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/de58d413-4f73-4258-bd2e-41f871f3f3e9/39855431502.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/390794f4-01a8-4d3c-bce0-fc72a955d760/robin_hood_disney_prince_john_plan.pdfIn PDF document text
    • https://43a2ba88-5de9-465b-b95f-6a4d82f2d06e.filesusr.com/ugd/dcbeda_ee615f5152a34c92a15c5ea484ac8314.pdf?index=trueIn PDF document text
    • https://b4095e1f-5e43-4c35-8b28-ff0c3185c247.filesusr.com/ugd/9cc3de_4a402b59253141fabd4e2e4c443c9c78.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e0c840ea-0625-47d7-9959-faacb3a9e2e6/tasazolijujegi.pdfIn PDF document text
    • https://891dfe3a-8969-4df2-b253-5ccc4ebbb7a0.filesusr.com/ugd/e66789_da2c36d1432b47c1a053372d0d94ca59.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ac889c1-9304-46d5-aa99-d74b267cfda5/pexejepo.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_off0000d90d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD90D 5048 bytes
SHA-256: 2ace576ebaf02041d957a175f9a7e6fd3cf583365a69794bff5ee76e8c990394
font_01_sfnt_off0000ea52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA52 10500 bytes
SHA-256: 420e79b9181ccda943d86116c7fd9a0c65ac3000d80c3ad0edc05e856faecfb5