Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5155b1894544d6d…

MALICIOUS

PDF

94.2 KB Created: 2021-03-31 20:27:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: ade2d95e3909a2ffdd6812ba0f35173e SHA-1: 94b4d2661b1a45c86bc1ea5d1f2fe11263e04409 SHA-256: d5155b1894544d6d8e3d6ff555d302e891fefaa1804961b6e4be97a19f189295
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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://kuzutuzo.ru/wix?keyword=l4d+pingtool+apk+2019 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4374532/normal_601153928a38a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454171/normal_5fcd8339e2f48.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469103/normal_5fd70f1910bb1.pdfIn PDF document text
    • http://ligovezedeje.iblogger.org/androidx_coordinatorlayout_gradle.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462339/normal_5fe5ec02b4190.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/ad1d5fd0-de10-437f-8663-5a01a431ebd5/10701014545.pdfIn PDF document text
    • http://jezuwujitek.epizy.com/como_citar_bibliografia_vancouver.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/31bdaed4-206a-4f94-bda1-53a35993ff20/transformational_leadership_in_nursing_practice._british_journal_of_nursing.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/193c1e13-7fe7-4160-bc30-86fda0695233/how_to_use_innova_obd2_scanner.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/75cdd852-47e8-417a-be0d-3ad36fd9922e/94614483594.pdfIn PDF document text
    • https://3dcfbd4a-ef33-49dc-a04a-0aaf5307c30d.filesusr.com/ugd/b47706_e4d6f8ce408940cbac4bfeca70e702fc.pdf?index=trueIn PDF document text
    • http://pibubirokur.rf.gd/cessation_nation_apk.pdfIn PDF document text
    • http://nulidofa.rf.gd/99314090760.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c8caaf17-4466-4c6f-8524-0de0fd9a33a7/xafevifuzarivuwesufib.pdfIn PDF document text
    • https://6f847715-c85a-45d9-ae5c-7c68cc800588.filesusr.com/ugd/6e100b_f1bd7a72ab214233affc96c4d4859916.pdf?index=trueIn PDF document text
    • https://383fd46b-cc41-47b7-9379-19c19d7bb1fe.filesusr.com/ugd/81c43a_76f25394c6e24d4c96b4cd7ad0e85f87.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/12b83b6a-8ff1-448f-92e3-983c049d00fa/zeluwesunobekalubukane.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e487c075-872c-45de-a17e-5b562ca5f7f9/88845668434.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/988571ca-a35b-48d0-acad-efc8b5f86228/89168864983.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00012bd5.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x12BD5 28116 bytes
SHA-256: 90191cd90894637eb708f1ea28490bd20fcc16ba142cf1a1a4c7fb5225abc5fa
font_00_sfnt_off0000f4d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D8 5100 bytes
SHA-256: 6f0df176e184549df13bcd41b1c74955bc2d7b195393aa9f0efcd316434406f4
font_01_sfnt_off00010648.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10648 10908 bytes
SHA-256: b4c070a7cd4a3db4f47d77b433a320ccff2fa2849e6796bad908aae3d9d10a3b
font_03_sfnt_off00015d72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D72 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3