Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab53f57705c63d2f…

MALICIOUS

PDF

73.6 KB Created: 2021-04-25 04:07:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: eabdbf4fc1ca38700a3f621f54f532dd SHA-1: 23471d85820f7f247f559e023bdc00acd3a914b3 SHA-256: ab53f57705c63d2f5737fe074dac62974fb56de4221341cb97c3c3e1400045ae
194 Risk Score

Malware Insights

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

This PDF document is classified as malicious, exhibiting characteristics of a link farm designed to redirect users to potentially harmful content. The presence of numerous external links, including one pointing to 'vilenefex.ru', suggests an attempt to obscure the true malicious destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://vilenefex.ru/strik?utm_term=dell+optiplex+960+audio+drivers+for+windows+10+64+bit PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4387052/normal_6067d0898dfd5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4487424/normal_5fcae5116b629.pdfIn PDF document text
    • https://seritixatot.weebly.com/uploads/1/3/1/0/131070849/6335055.pdfIn PDF document text
    • https://dijovenop.weebly.com/uploads/1/3/4/7/134705939/5772767.pdfIn PDF document text
    • http://jinevul.mygamesonline.org/25576581896.pdfIn PDF document text
    • http://kolegutoravi.mygamesonline.org/40169411901.pdfIn PDF document text
    • http://zesegalos.scienceontheweb.net/active_directory_tutorial.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://54a0e2cb-796f-4f80-9aaf-d11633176b06.filesusr.com/ugd/b0c554_7470d000f99c48e0b9261422de25dc8a.pdf?index=trueIn PDF document text
    • https://44034db3-6cdd-4729-adf3-7ccd6afcf354.filesusr.com/ugd/9fe9cc_79bbb95b55624e459896b170871bf17b.pdf?index=trueIn PDF document text
    • http://zegetafirotazaz.atwebpages.com/31656674776.pdfIn PDF document text
    • https://9c12218e-e157-4070-b33f-4467b3cb42bb.filesusr.com/ugd/0c60a0_6daad7a3f01d43be8fc5a6d12bc17549.pdf?index=trueIn PDF document text
    • https://314a97e4-cc7b-499c-a999-42b15fb65c39.filesusr.com/ugd/fa4a73_b4ee4426887c44de8e5ed8296ae91e34.pdf?index=trueIn PDF document text
    • https://d56a38bf-d62e-453c-9b5b-5b2fe88aea46.filesusr.com/ugd/359e64_f1ae35d5fb8a469e99650cbedcbe9873.pdf?index=trueIn PDF document text
    • https://56a7be67-7dca-40da-a973-69ad719fb73b.filesusr.com/ugd/fedf23_f5d30d73113a483183ade5815944799f.pdf?index=trueIn PDF document text
    • https://587b455d-cc79-4428-8e80-a8b75ce23bca.filesusr.com/ugd/021ec8_f95bf87ab4214896a3136b6fe3057b62.pdf?index=trueIn PDF document text
    • https://a40b6db0-1679-4e03-879f-ac5827b9aa7d.filesusr.com/ugd/dba42a_083f13d6fc824eee973e65f4912f62ce.pdf?index=trueIn PDF document text
    • http://pikubub.onlinewebshop.net/kogosanaxog.pdfIn PDF document text
    • https://df1882fa-13c5-42f1-8438-577935b594b9.filesusr.com/ugd/91932b_c6cb2b109f92442f8c1c6309334d7e7f.pdf?index=trueIn PDF document text
    • https://627f215e-41ba-4aa4-9906-5f9f9d117739.filesusr.com/ugd/8ab72e_4d49fa2f788847ebae8804c507d1bd36.pdf?index=trueIn PDF document text
    • https://61069a5e-3c5f-4884-a3c7-8c7552058b74.filesusr.com/ugd/0789d5_39e01aaa047243ffb001941a8bf0d64c.pdf?index=trueIn 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_off0000dfc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC2 5988 bytes
SHA-256: 06b3345facb8627dd520ea2d91319ee51db3e13b041ec07901aa675ec8efc26c
font_01_sfnt_off0000f44c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF44C 10956 bytes
SHA-256: c2935b4f9bfe14620c41d6cc666571b54a85304684251d2c8a9289a9b88fb990