Malicious PDF — malware analysis report

Static analysis result for SHA-256 58b96c23abd047e6…

MALICIOUS

PDF

75.0 KB Created: 2021-03-22 23:20:56 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 7b2f9b8f1387cb28a03a08cf52dec3af SHA-1: 27a431f9ca23dd039b932ed96cc5a0999ac519c2 SHA-256: 58b96c23abd047e63206c0fe1ce40f64a262d02c0785ccc72cdb9992c3f81f7f
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable domains, suggesting a link farm or SEO spamming operation. The document body, though heavily obfuscated, contains keywords related to 'free adblocker browser apk old version', indicating a lure to download potentially unwanted software. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://leonvi.ru/wix?keyword=free+adblocker+browser+apk+old+version PDF link annotation
    • https://cdn.sqhk.co/motuxeneb/fhcX5ib/78456244525.pdfIn PDF document text
    • http://shop-onlain.fun/totally_accurate_battle_simulator_free_download_apk_pculuut.pdfIn PDF document text
    • http://bumosid.getenjoyment.net/belajar_excel_untuk_pemula.pdfIn PDF document text
    • http://gta-msk.ru/bakudufagexiselesaugk6.pdfIn PDF document text
    • http://zemesod.getenjoyment.net/gewarudadodega.pdfIn PDF document text
    • https://cdn.sqhk.co/nujusowidom/bGgiibn/rasudutexilijituxuguti.pdfIn PDF document text
    • http://extraterrestrials.space/bozitoge7mnpj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/gasodamuza/bluebeam_revu_2018_msi.pdfIn PDF document text
    • http://zubiluwetij.myartsonline.com/63118776489.pdfIn PDF document text
    • https://s3.amazonaws.com/pafiganovavi/wilmington_bible_study_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/jozaponi/vifenuforitugexiri.pdfIn PDF document text
    • https://e510c2d5-567e-4a96-89ff-abc18316baf7.filesusr.com/ugd/8a9bcc_c0294746a39f41b9b42363fbd38967fd.pdf?index=trueIn PDF document text
    • http://kewevagisugimuw.onlinewebshop.net/angular_js_with_asp._net_mvc.pdfIn PDF document text
    • https://ad858f6a-7bbb-416d-9365-e04d7986ed9b.filesusr.com/ugd/3c9ac1_7157f85a738e4b2abbc82b64fc4eb81a.pdf?index=trueIn PDF document text
    • https://e0271a52-a7af-48e9-8a99-924ce320ec62.filesusr.com/ugd/be5703_2f999f75cdb14122b5afd3b0759da8a4.pdf?index=trueIn PDF document text
    • https://7abbf572-6989-4614-8246-9d5ba34cd238.filesusr.com/ugd/af841b_f5f9108acb444d378acd7ecf7e8cf51d.pdf?index=trueIn PDF document text
    • https://5057b38b-f250-4925-a5fd-2dbc054a2c1f.filesusr.com/ugd/25ee37_822d04dcfa1c47e7b955ca6e7c4238fa.pdf?index=trueIn PDF document text
    • https://eadb47d6-6712-4ecd-aa5a-2cdcf2d90b86.filesusr.com/ugd/c844bf_07985101cbea4c8f887ee05ed9d84f96.pdf?index=trueIn PDF document text
    • https://66c7139a-03c0-45fe-98d3-e817d1e01442.filesusr.com/ugd/de2db5_07ecd4e168d046c397fb0d3a7670bfa0.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_off0000d0a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0A0 5376 bytes
SHA-256: d831be65662e18f15e8ffa9c3f8be8bcb85493d7ab681abf938ef11cb5ead836
font_01_sfnt_off0000e30e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE30E 10920 bytes
SHA-256: 14acc59e122e0ce00e57fe5a2031dca0ed697c2b4a05b6ad45411df511db649a
font_02_sfnt_off000108a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A4 16212 bytes
SHA-256: 4a8acf2c5b638d33c0dbd889610eca28025136dbdfe8f3f84084fcd7b426ca8c