Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1797ed940591122…

MALICIOUS

PDF

70.5 KB Created: 2021-04-01 01:01:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: f590d95db0a7f1434132c72781a7cc5b SHA-1: 1da2482b63a9e7fed3abd52fa7e61f70e14495b1 SHA-256: b1797ed940591122b86b55b13faf0f77891db9769a206031f08c188e99a600b5
244 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to disposable hosting, and one critical link to a known malicious redirector. The document's content, though obfuscated, appears to be a lure for a chemistry worksheet, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier further support its malicious nature.

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/wix?keyword=ap+chemistry+stoichiometry+worksheet In PDF document text
    • https://cdn-cms.f-static.net/uploads/4401694/normal_5fe69c7a3720d.pdfIn PDF document text
    • http://fezatubiwe.getenjoyment.net/que_son_los_alimentos_transgenicos.pdfIn PDF document text
    • http://consumer-data-protection-bureau.com/badezegunilorunesabmtci.pdfIn PDF document text
    • http://zobevewobuka.22web.org/draw_me_nearer_piano_sheet_music_free.pdfIn PDF document text
    • http://tidexozi.22web.org/learning_american_english_conversation.pdfIn PDF document text
    • http://astropsychology.site/business_administration_degree_courses_onlinejbpk4.pdfIn PDF document text
    • http://profapp.pro/agenda_docente_2020_para_imprimir9k1k3.pdfIn PDF document text
    • http://dakisemakegag.sportsontheweb.net/affichage_obligatoire_2020.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4447662/normal_5fc930e1d2428.pdfIn PDF document text
    • http://fulokixowo.scienceontheweb.net/how_to_start_an_outboard_motor_without_a_key.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444113/normal_603cbd93b36c3.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/99cc21ff-5429-467b-831b-f359cd58b144/jowuronolovokiwur.pdfIn PDF document text
    • http://bigapenegig.atwebpages.com/josagalurabu.pdfIn PDF document text
    • http://nenilezum.epizy.com/masej.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e1ee94dd-bb4e-4f69-8021-f6cab59d462c/sipedulexanitukazafumed.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/11bbbae4-daad-4c6b-a899-85e2cef97fb8/64773854299.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3f022089-f2c3-416e-8e1d-da9cd070c6cc/buxufurabalafomazazaseti.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/53d8f1d9-87c0-41f8-86d8-b4e4228e229b/fawavikimiveliferadul.pdfIn PDF document text
    • http://dowafirowelumex.atwebpages.com/zuponexatakojiz.pdfIn PDF document text
    • https://1747caf2-50c5-4ace-8f30-8d3f4e2f7d49.filesusr.com/ugd/017962_fb67facaf2ca40cfa4b63f270e39890a.pdf?index=trueIn PDF document text
    • https://14535e1a-360a-4d01-a655-fa33e115c80e.filesusr.com/ugd/b222ea_f40833d017d9436bb7381010e4fb63d1.pdf?index=trueIn PDF document text
    • https://03f57db0-fbcf-46ec-8713-21b5992b8512.filesusr.com/ugd/455f95_df20b7e8ef6e4002a7cd3716169e9f7a.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d670.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD670 5176 bytes
SHA-256: f18cc3cdc1d8290256ee380db85d2682bc1d13f2f9fe8d5a1bc64ec000e9279a
font_01_sfnt_off0000e7fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FE 10144 bytes
SHA-256: 2a795f40bb691226d7d0ad36d768016683cf4047b82a7075f0dfb8b0b0410347