Malicious PDF — malware analysis report

Static analysis result for SHA-256 a55dc3133d4d8991…

MALICIOUS

PDF

66.7 KB Created: 2020-12-17 10:34:11 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-17
MD5: 5d98faac8028f30add0a8d2602476151 SHA-1: 7e7e4c8c652049b6c74dd3f37d12abd658afa49b SHA-256: a55dc3133d4d8991a3bfc09fa54e4ae98bfb527bd31be1fa038379fde150dc76
96 Risk Score

Malware Insights

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

The PDF file contains a lure related to the NHS, directing the user to a suspicious URL. ML classification and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the embedded URI is the primary indicator of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://trafffe.ru/123?utm_term=the+four+crumbling+pillars+of+the+nhs PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4393751/normal_5fd13c84e2d2a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369762/normal_5f8aacef40fc7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383146/normal_5fa9c9b542716.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369935/normal_5fd164289cf24.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454821/normal_5fd27aeeb06be.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/17ddfde8-f320-420c-ab96-442032957039/roland_jazz_chorus_60.pdfIn PDF document text
    • https://s3.amazonaws.com/tigovatolis/88566897671.pdfIn PDF document text
    • https://static1.squarespace.com/static/5fc0e155104edf1d7780ac3e/t/5fc14b07173fb5383bd2381d/1606503176863/spelling_test_template_15_words.pdfIn PDF document text
    • https://static1.squarespace.com/static/5fbce344be7cfc36344e8aaf/t/5fbcf6bb29c5e2669025560c/1606219451784/why_average_bond_enthalpy_is_not_accurate.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/760164f4-d56e-44b5-adac-c255098f8a62/chief_administrator_example_sentence.pdfIn PDF document text
    • https://s3.amazonaws.com/vezumobigodub/manual_for_timex_expedition_watch_indiglo.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_off0000c9d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9D1 5516 bytes
SHA-256: c3b338ef1131c548b2a8cdbe92c1d469f6c1d6029de28721f69a8b163d6ff8cd
font_01_sfnt_off0000dc67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC67 9924 bytes
SHA-256: 2b7534019af071ed6890db90e1ce136255f958d08ce4500f5b0cb601a86241aa