Malicious PDF — malware analysis report

Static analysis result for SHA-256 198b0f31aecd79d7…

MALICIOUS

PDF

89.4 KB Created: 2021-04-04 09:39:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 268101abb77fde179881da27dfe72d24 SHA-1: 5a4930d09404c82714194539ebe52b2231201d7e SHA-256: 198b0f31aecd79d774b7f0e17cd401f5981c2548c03bff12c026877adcfec952
226 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. It uses a password-protected-archive lure and a seed-phrase/secret-recovery lure. 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 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://crophysi.ru/award?keyword=brute+force+pdf+password+kali PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4381756/normal_60557ac62f2a0.pdfIn PDF document text
    • http://mini-camera-super.club/the_winters_tale_noteslumz7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464068/normal_604f593768897.pdfIn PDF document text
    • http://tevfikyuce.xyz/generational_diversity_discussion_questions1cndm.pdfIn PDF document text
    • http://hookup154.online/compare_and_contrast_fiction_passages_5th_gradetkpxq.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471514/normal_601d0180af674.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376854/normal_602a84a170b54.pdfIn PDF document text
    • http://smartradiobf.ru/windows_10_os_for_android_mobilecdkc9.pdfIn PDF document text
    • http://subonus.ru/how_to_reset_a_nighthawk_carbon_monoxide_detectordh1re.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475570/normal_602708dbbfd13.pdfIn PDF document text
    • http://tixanijematewe.mypressonline.com/pizenujewawodixa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://486bfeb6-87d8-40a3-812f-3449909c9139.filesusr.com/ugd/81b904_92a444624c7a41e288d1cd9e7d975dde.pdf?index=trueIn PDF document text
    • https://92fed17e-af34-466b-b3fe-38cd9ef27699.filesusr.com/ugd/192d58_0eb81f9a63dd4b90aaeb2210ca7f9287.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dinilederu/lets_build_a_cladogram_worksheet_key.pdfIn PDF document text
    • https://s3.amazonaws.com/donake/86743542461.pdfIn PDF document text
    • https://f6b99bba-f064-431f-ab68-6eacb91b2703.filesusr.com/ugd/35e1ce_ba58b01b6305494982ccedfc26feeeae.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/rawesaragegugar/79368261981.pdfIn PDF document text
    • https://0aa989e7-076c-475f-bc22-fff5ae310860.filesusr.com/ugd/b44be6_877151b420ed4dff930127dbc791bcfb.pdf?index=trueIn PDF document text
    • http://gamelaluwer.myartsonline.com/alcanos_alquinos_y_alquenos.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_off00011d5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D5E 5356 bytes
SHA-256: dfc478470224e95bfd1e9f7341f956ab06bc95d89fad3011667f5273ef907c4c
font_01_sfnt_off00012fbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FBE 12044 bytes
SHA-256: 7fb584e609c4cd142491518fd9122ba4bcd515b39b715ed33b2ce0316f3e480a