Malicious PDF — malware analysis report

Static analysis result for SHA-256 17cf8e762ae9356c…

MALICIOUS

PDF

77.3 KB Created: 2021-04-05 01:21:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 929706f6a05bd29af7a04ba018ee61d2 SHA-1: b13867d39d1bbd33cea0545e8523a115b81eb074 SHA-256: 17cf8e762ae9356cdd994e86b642ca9df466c5b8b5c9ae06040e39f286f39802
126 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, identified as a link farm. The ML classifier strongly indicates maliciousness. The primary purpose appears to be directing users to external sites, which could host further malicious content or be part of an SEO manipulation scheme. The presence of multiple disposable hosting domains and unknown reputation URLs supports this.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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://druttle.ru/award?keyword=anthropometric+data+for+interior+design+pdf PDF link annotation
    • https://cdn.sqhk.co/rolileduvof/jdMwDnQ/lobemuxadu.pdfIn PDF document text
    • https://gedarimetesuja.weebly.com/uploads/1/3/1/3/131398281/fotulegep-migomaf-zapup.pdfIn PDF document text
    • http://lessonsonline.site/8691520825j6u8d.pdfIn PDF document text
    • https://sovomebidug.weebly.com/uploads/1/3/1/3/131379042/d0480e6021ac.pdfIn PDF document text
    • https://cdn.sqhk.co/wibononuve/tgcRheY/example_abstract_for_science_report.pdfIn PDF document text
    • https://xisobapujizutu.weebly.com/uploads/1/3/4/5/134585888/dowunatizudivakebu.pdfIn PDF document text
    • http://cetop.xyz/puwovi3i1a1.pdfIn PDF document text
    • http://callup.today/2654045478647g5x.pdfIn PDF document text
    • https://legelopupusida.weebly.com/uploads/1/3/4/3/134350366/biwiwapanebomit.pdfIn PDF document text
    • https://cdn.sqhk.co/zerurukoraju/jdbNlgh/pogopelamofuzuravikizi.pdfIn PDF document text
    • http://ovca.space/zawamepajegigemoliidt8c.pdfIn PDF document text
    • http://torchland.xyz/reglamento_de_transito_celaya_gtostx92.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/4a1abc64-3b99-4213-b412-6aa940635d82/alesis_dm10_mkii_pro_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/00d10890-4975-4048-b9fe-ac279fe18ba0/what_is_bilingualism.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e0a5f5d1-f994-4e49-ad77-d10fd203895c/25994484316.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c371b3f6-78e5-4cac-acb7-04d39c362fe5/27587064724.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/17222acc-aa86-4b67-bbcd-e59ec70c4975/how_to_adjust_bobbin_tension_on_brother_pe770.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c561578a-00ef-484a-bc13-ca8e63bdab31/how_to_clean_fisher_price_bouncer.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_off0000efe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE0 5528 bytes
SHA-256: 187236e4788b88b6c9e6d0b1ba7a5cb76442227a53a7de19ab0daa46b970328e
font_01_sfnt_off0001027e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1027E 10968 bytes
SHA-256: d62dbfc63b3437e62ae83d612b535a72fed1f337d4a8618dbbb2a6427ce468f9