Malicious PDF — malware analysis report

Static analysis result for SHA-256 b135d78f81e0b4a9…

MALICIOUS

PDF

61.8 KB Created: 2020-12-31 21:41:28 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 788eaa47b42845560f52149372c7cc6b SHA-1: 38c955d5f997a9723756b5a9f22ebab44010bc9d SHA-256: b135d78f81e0b4a9bbb86b08af6d6ea9e00bfede51e7b501f2b05f878615ee72
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with one heuristic specifically identifying a 'PDF_SEO_LINK_FARM' pointing to various PDF files. The primary malicious URL, 'https://traffine.ru/123?utm_term=the+great+gatsby+chapter+6+study+questions+answers', is likely used for phishing or to host further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

Heuristics 5

  • 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.
  • 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://traffine.ru/123?utm_term=the+great+gatsby+chapter+6+study+questions+answers PDF link annotation
    • https://dozisinabi.weebly.com/uploads/1/3/4/6/134646642/9f65ef5.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/zugutixe/cya_soccer_uniforms.pdfIn PDF document text
    • https://s3.amazonaws.com/bawalidamovidud/sufugik.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5879adc3-b3a5-4728-a575-3e222afd95a6/como_se_juega_el_futbol_y_sus_reglas.pdfIn PDF document text
    • https://s3.amazonaws.com/netinuwa/adobe_photoshop_elements_2018_electronic.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/75826aa8-ce48-477c-9596-8880c7f66dca/38966635015.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2525e0dd-9de2-4fce-89dd-e8dea5c30ba3/nuxaxejobo.pdfIn PDF document text
    • https://s3.amazonaws.com/suxiweke/lagu_on_my_way_dj_dangdut.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8861d168-7aa5-45c4-90c5-b4535cb43313/fiteruzibevurepuve.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_off0000b514.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB514 5864 bytes
SHA-256: e0e71b701fe9de049e54fa0c618118be3f2d216c3487ed6c64d8b9a5a305aec6
font_01_sfnt_off0000c911.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC911 9860 bytes
SHA-256: d4f850395af0a13eff99acc3dffeba4d1556267831101b31de1abbba9464bc62