Malicious PDF — malware analysis report

Static analysis result for SHA-256 83b187a48b396ca3…

MALICIOUS

PDF

76.1 KB Created: 2021-02-17 18:28:04 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-31
MD5: dda2a41681c35693d3f6d2b8e2bfe6b8 SHA-1: bbccafaa76194e61ccd026d932b151857cdf42aa SHA-256: 83b187a48b396ca367737672201720352e53b5456da1e8993055f0721d6df85a
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links pointing to various domains, many of which appear to be disposable or low-reputation. The ClamAV detection and ML classifier strongly indicate maliciousness, specifically a phishing or trojan threat. The heuristic PDF_SEO_LINK_FARM suggests the document's primary purpose is to act as a gateway to a network of SEO-optimized content, likely to distribute malware or conduct phishing operations.

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
  • 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://leonvi.ru/strik?utm_term=convertir+gramos+a+mililitros+cocina PDF link annotation
    • http://gbo.guru/brand_awareness_and_brand_image137tm.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4365562/normal_5fe222b72b1be.pdfIn PDF document text
    • http://bluebadgeapproval.com/naydra_horn_farm9ckxj.pdfIn PDF document text
    • https://zorivaleguzovul.weebly.com/uploads/1/3/4/5/134596353/cfa24c00cf.pdfIn PDF document text
    • https://kuvinonufero.weebly.com/uploads/1/3/4/3/134307364/suzikuzixo_fasuvot_rolupot_tabibe.pdfIn PDF document text
    • https://laxivaxof.weebly.com/uploads/1/3/0/8/130874385/7961105.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390383/normal_5fd864fdd8092.pdfIn PDF document text
    • http://businessmentality.com/abide_with_me_chords8vj74.pdfIn PDF document text
    • https://cdn.sqhk.co/vufebevefo/aahfMgj/project_management_jobs_colorado_springs.pdfIn PDF document text
    • https://bunozejat.weebly.com/uploads/1/3/4/3/134387809/4750202.pdfIn PDF document text
    • http://ig-mediateam.net/96352810612qaeov.pdfIn PDF document text
    • https://zokilare.weebly.com/uploads/1/3/4/7/134767859/latopizanozegos.pdfIn PDF document text
    • https://xibimitavidin.weebly.com/uploads/1/3/1/8/131871740/3407280.pdfIn PDF document text
    • http://beststudent.space/xuronatezod3f6g.pdfIn PDF document text
    • http://gratoram.site/black_sabbath_changes_sheet_music_free8z2h7.pdfIn PDF document text
    • https://cdn.sqhk.co/javomekoru/gfOOajf/nakeromerukavonojexa.pdfIn PDF document text
    • https://cdn.sqhk.co/musezikuzapi/iy9QDzE/wudidi.pdfIn PDF document text
    • https://gifiboluf.weebly.com/uploads/1/3/2/6/132681188/6420566.pdfIn PDF document text
    • https://bapanezuginu.weebly.com/uploads/1/3/5/3/135310050/7806364.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482407/normal_5fe9e4d6ef4d6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457843/normal_602a3f79d91a1.pdfIn PDF document text
    • http://slampochka.ru/cambridge_dictionary_for_pc_offlineus9r9.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000ea59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA59 5084 bytes
SHA-256: a369779890865f2a9432eb465d5b0ac915f2ac86293e2d39fc07d6c03b7d08d1
font_01_sfnt_off0000fb93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB93 12652 bytes
SHA-256: 933ed353c29e3a6109b7e8eaa8d1447e7ee934fc1425a0b9e2f2d1357667ce13