Malicious PDF — malware analysis report

Static analysis result for SHA-256 5efc66fd4f0a4816…

MALICIOUS

PDF

75.8 KB Created: 2021-03-11 10:17:31 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 2f79c4098ed9bba08d5308fae4adaf78 SHA-1: 736286a7ec7f82cd2ccdedac36d3787a59ef1f9d SHA-256: 5efc66fd4f0a48166f79c93e027200b144b282e3b7299099cbd0750721bbc296
244 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to disposable hosting, suggesting a link farm designed to distribute traffic or host malicious content. One critical heuristic identified a link to known malicious redirector infrastructure, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection further support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://crophysi.ru/123?utm_term=template+for+inventory+control In PDF document text
    • https://ginadilu.weebly.com/uploads/1/3/4/7/134768391/zuwogododikiv.pdfIn PDF document text
    • https://vororesefuvemux.weebly.com/uploads/1/3/0/8/130813496/bd072103.pdfIn PDF document text
    • https://safalijig.weebly.com/uploads/1/3/1/0/131070993/seposugid.pdfIn PDF document text
    • http://sazasebum.iblogger.org/15779809431.pdfIn PDF document text
    • http://xijogeziku.66ghz.com/hydrogen_peroxide_3_sds_sheet.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/fedure/97654022510.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/14d2061d-1b8f-4964-a10c-7d207892abb5/what_vegetables_not_to_eat_on_a_keto_diet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/40b9d883-c9a1-4a3d-b630-c3197c67b203/why_is_samsung_fridge_not_making_ice.pdfIn PDF document text
    • http://lobabixagoxip.rf.gd/19384693793.pdfIn PDF document text
    • http://dabemekos.epizy.com/guludavugafafoja.pdfIn PDF document text
    • http://vobuxex.epizy.com/hdfc_new_immediate_annuity_plan.pdfIn PDF document text
    • http://notalopelovawu.epizy.com/cisco_packet_tracer_version_5._3.pdfIn PDF document text
    • http://lotidasifiteg.epizy.com/street_fighter_2_windows_7.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/19d5353a-026e-4c6a-985b-4904969551d4/fomevuwuvezitojetek.pdfIn PDF document text
    • https://s3.amazonaws.com/bejikefowu/about_us_page_template_for_blogger.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b50d197e-b0cf-4ec9-9a3e-5cbf9d7ceecf/google_cardboard_folding_instructions.pdfIn PDF document text
    • https://s3.amazonaws.com/tawovojo/31231484015.pdfIn PDF document text
    • https://s3.amazonaws.com/lemefofutomapox/sni_bioplastik.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/87969314-b0a2-42c0-8ec0-22c42518d2c1/reading_comprehension_test_grade_10_online.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ceefad45-a371-407a-b629-dc567e1dad50/hoover_windtunnel_max_capacity_pet_upright_vacuum_review.pdfIn PDF document text
    • http://vebavibokifoko.epizy.com/37300718901.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a58f1bde-8346-4fe3-9495-0a13b54bbbe6/foditudibijukuvoxujen.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/31af28dc-1fa7-4232-96cc-9718305bf33d/12687693367.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f021eae2-ca11-46d1-bb0c-81655efa575a/85896264317.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_off0000eefc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEFC 5092 bytes
SHA-256: 9cfbe3a3c00f4fc9c7901fc5b74aeb86f4ce44c0fcc95ed4fe9b0ed7291e2a82
font_01_sfnt_off00010049.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10049 9840 bytes
SHA-256: ccd9391e9bb9e194e5c7b148d169004c9ec231b9053f3caeda32f7269596ccfd