Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f817f3981c9670b…

MALICIOUS

PDF

72.9 KB Created: 2021-06-09 08:48:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: e5242c5e42cad77dbb27237dfee6a3d3 SHA-1: a88509748d06d8b2913e495280647b26b64168f4 SHA-256: 8f817f3981c9670b15e0ab14b9a51b86cf7df29ff8e1ab8862eb4bd7c9d40a70
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file contains a large number of external links pointing to disposable hosting services, indicating a link farm designed to direct users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

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://catamma.ru/pbw?utm_term=internet+cafe+business+proposal+pdf PDF link annotation
    • https://sezorataxij.weebly.com/uploads/1/3/4/6/134600708/dejagoriw_joluno_zoterorajepefir.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417992/normal_6008c4eeaa8f3.pdfIn PDF document text
    • https://fumubesoxumus.weebly.com/uploads/1/3/4/4/134485348/3cde9f09f.pdfIn PDF document text
    • https://towizitubozabo.weebly.com/uploads/1/3/5/4/135400713/4832430.pdfIn PDF document text
    • https://fuwodeku.weebly.com/uploads/1/3/6/0/136095673/kulaw.pdfIn PDF document text
    • https://fepapiwepum.weebly.com/uploads/1/3/4/3/134382013/wudadiwofidu-wasapinewavor-porazomuzoga-tolege.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4421624/normal_60018f374f326.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483336/normal_60bbacdba8ee5.pdfIn PDF document text
    • https://pipulelinukebe.weebly.com/uploads/1/3/4/3/134364851/e4d3b.pdfIn PDF document text
    • https://foniliwis.weebly.com/uploads/1/3/2/6/132695455/dujapivaxavevi-fobef-lefotizoko-xusuwijejilenik.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/5eaa874c-255c-493f-b070-b3daaed25acb/ratios_and_proportional_relationships_6th_grade_worksheets_answers.pdfIn PDF document text
    • http://daxulesep.pbworks.com/f/waxodipopov.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/965f1cc7-a0a1-4e5d-bf4a-968c3db919cc/how_to_put_yamaha_moto_4_in_reverse.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9b6c30b3-6a90-45e9-ac2a-5eb0e3a704d2/pretty_little_liars_book_collection_in_order.pdfIn PDF document text
    • http://lifuzopa.pbworks.com/f/62013334535.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/81ddbcbd-3014-48b0-95cb-a0e02558ee25/86943202922.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9f928f85-6cf9-46e2-b00c-740958801af1/jack_and_the_beanstalk_story_pics.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8ee96d42-2fff-473c-8acd-7fbe981d3190/the_chaser_by_john_collier_meaning.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_off0000dfb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB4 5224 bytes
SHA-256: 823682db53570f7b736e889c70c177645b2c20f652986a97cad54dfcb4073641
font_01_sfnt_off0000f17f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF17F 10724 bytes
SHA-256: 03afa7994699ae8c06b4a50e7611c50ca3d6b39e3f211a6c6e0bd2de68a60a50