Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a4eb52fdd27ac7f…

MALICIOUS

PDF

44.8 KB Created: 2020-10-26 13:56:25 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 2ead52858d0fc21b5d6589dbd5cd6477 SHA-1: e96ff67ee36d1c764f66f7b80363d9cb692e2fc7 SHA-256: 8a4eb52fdd27ac7fae8274d39a7e86a762e53db78008e781ab9003834d97c485
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many pointing to disposable hosting or redirector services, indicating a link farm designed to distribute traffic. One critical heuristic identified a link to known malicious redirector infrastructure, suggesting a phishing or malware distribution attempt. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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://ggtraff.ru/strik?keyword=sittin+on+the+dock+of+the+bay+vocal In PDF document text
    • https://zodowiburasuv.weebly.com/uploads/1/3/4/4/134448486/2047463.pdfIn PDF document text
    • https://nugemezan.weebly.com/uploads/1/3/4/3/134359438/5598760.pdfIn PDF document text
    • https://sabidodavo.weebly.com/uploads/1/3/1/4/131408103/daneka-vafovowolone-gosir.pdfIn PDF document text
    • https://fusajebotiv.weebly.com/uploads/1/3/4/3/134320253/fa629a168a1ef9b.pdfIn PDF document text
    • https://misopiwulasi.weebly.com/uploads/1/3/1/8/131856666/murarofabesudo-sasab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373788/normal_5f8e65a9e0ebd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383805/normal_5f905e347866f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371272/normal_5f8d559869713.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366004/normal_5f87179acd9b8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370076/normal_5f8829c84306c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380079/normal_5f94ffd28e593.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375206/normal_5f8a844e44ea6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379045/normal_5f903a89edc9e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386361/normal_5f909f1f55fe5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366357/normal_5f8ba51ab5fa5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367674/normal_5f893685f2009.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379385/normal_5f941392daa20.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0440/7784/2597/files/ligixomipegasopawiji.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0505/5171/8070/files/volvo_articulated_dump_truck_operator_manual.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0481/9648/5277/files/repsol_multivalvulas_10w40.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/4256/9368/files/history_of_islamic_banking_in_pakistan.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0484/0826/4862/files/drafting_and_pattern_making_book.pdfIn PDF document text
    • https://s3.amazonaws.com/memul/55386682893.pdfIn PDF document text
    • https://s3.amazonaws.com/jamokaroxoj/sewing_machine_motor_repair.pdfIn PDF document text
    • https://s3.amazonaws.com/penefelomiju/seneripekajurat.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_off00006e02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6E02 5304 bytes
SHA-256: 19910d547271b924f288b3a57534f9698021a1dbe07a31238282a1de5f248da6
font_01_sfnt_off00008012.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8012 10852 bytes
SHA-256: 2bf7e380f5528f63fa06e07e7426366e0d5be1205e8e85c1a310795751e7fc24