Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c1c3f8709f6ed76…

MALICIOUS

PDF

80.1 KB Created: 2021-03-18 06:49:27 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 2dcd3a3a86698bfdf62cc6685376100d SHA-1: d868f0d8c28df5c5a2f212f28dd83015aa2643ea SHA-256: 4c1c3f8709f6ed76bd48bc7dbb39c01ef18947c56b7120e95c4b4a859c0105e6
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 hosting, suggesting a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://dugedepap.ru/award?keyword=trastornos+del+metabolismo+de+lipidos+pdf PDF link annotation
    • https://laxukiwu.weebly.com/uploads/1/3/1/0/131070933/pesupixag-rufemamos.pdfIn PDF document text
    • https://cdn.sqhk.co/buzovegom/fih8Ggj/chrono_cross_reminiscence_piano_sheet_music.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446770/normal_60257e4ea2c88.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422897/normal_6017ad6b4cf74.pdfIn PDF document text
    • https://cdn.sqhk.co/jelasusoved/ajjjba0/fufigi.pdfIn PDF document text
    • https://ruxibudowivuk.weebly.com/uploads/1/3/4/7/134728491/xiwevotifezere.pdfIn PDF document text
    • https://zenibevakuziva.weebly.com/uploads/1/3/0/7/130739170/7884960.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://f26e6bca-ce10-4524-9610-ed5ef7c8d48b.filesusr.com/ugd/ac8c68_eea294c6228b4071b00ef9a7235aa094.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wovedukevikov/stanley_600_amp_jump_starter_how_to_use.pdfIn PDF document text
    • https://50b44c92-959e-4a15-bf83-93d6b2b518d6.filesusr.com/ugd/3ed44c_cb8832b6b15e438786508d3c82044e8c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e6706ec6-cc5a-4fe9-a1f6-c29d1db284b4/99687508127.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5747b449-b747-4dbe-8efe-9e40116195be/mevibobuxigefiwaxotove.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/20af4c0d-e1d8-4a70-b13d-e6bba0cccf7a/langston_hughes_high_school_alumni.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c03e9e7c-6b44-4f31-b48e-eacf25383fd2/kowadadazu.pdfIn PDF document text
    • https://s3.amazonaws.com/dubiditiginowo/funurogunovokidopekafeb.pdfIn PDF document text
    • https://s3.amazonaws.com/rivazixexuguri/setipipifaxadereburi.pdfIn PDF document text
    • https://s3.amazonaws.com/vososasoxumete/vamuvetulosedisa.pdfIn PDF document text
    • https://03df18d0-0a94-4077-8b44-1f3cf8b7c870.filesusr.com/ugd/23a6c3_3a50f3db2e6146328faf3e43b95a38c8.pdf?index=trueIn PDF document text
    • https://74df6fe0-557b-4e47-8461-f2df536053d0.filesusr.com/ugd/4dcf4e_59a0925e6ec14bfeb66a87eb3b7d203c.pdf?index=trueIn PDF document text
    • https://1cd0d4d5-11d4-440c-a307-81f73801f601.filesusr.com/ugd/f0e51d_ad4c53b16ffa430f808d6cce2b19b54d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/2a40a32d-18cc-4f36-b706-b95cba27c296/tai_chi_sword_instructional_dvd.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_off0000f8b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B4 5276 bytes
SHA-256: 944cbc9cac8be03d879502d02c40d719f5ee875a0e39ba8807aa0e5ba3bed17e
font_01_sfnt_off00010a82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A82 12012 bytes
SHA-256: 68aa6a2a1bfa7fee21133553fb4e2549c7951a4b4d4b21010f3580ab5a32c12e