Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f4631c1f584d667…

MALICIOUS

PDF

69.1 KB Created: 2021-05-28 07:42:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 12441fcdc91685053e9e90c48b7316aa SHA-1: 2f7a0ff516940011e41a900f6efc5b8b278df4e7 SHA-256: 3f4631c1f584d667bec56d8f923aa0d79fd4a4873ecb102c5c01495acff77ea7
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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://botokaw.ru/strik?utm_term=grade+8+mathematics+platinum+textbook+pdf PDF link annotation
    • https://zirefugat.weebly.com/uploads/1/3/0/7/130740019/1620733.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4426408/normal_5ff4059ebb623.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417128/normal_601b72ae7facb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457008/normal_5fec95201c428.pdfIn PDF document text
    • https://molesomux.weebly.com/uploads/1/3/2/6/132681378/8192315.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385422/normal_6034793a11e7f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459939/normal_601ee5ecd2403.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448094/normal_60132a04d39e3.pdfIn PDF document text
    • https://zerebutaravuna.weebly.com/uploads/1/3/5/9/135965874/zorunetulopamo_wixova_bogirul_navenutefumak.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495058/normal_6050c4004fbd4.pdfIn PDF document text
    • https://bowodazuludov.weebly.com/uploads/1/3/4/7/134700376/fazebuguroturu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469106/normal_6022f9b1ba8f4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408976/normal_6023468798de2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446398/normal_603ea0ef68f52.pdfIn PDF document text
    • https://duvinibekumexeg.weebly.com/uploads/1/3/4/6/134677329/2550184.pdfIn PDF document text
    • https://gubotejulide.weebly.com/uploads/1/3/4/3/134380330/1a1c81e19e3e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4466154/normal_5fd073ae7abae.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/2155aa39-aaad-4796-bc1b-763ade41c2ad/96968955058.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1dd77853-ed1b-4783-abb0-45f35775bc60/12_irrefutable_laws_of_leadership.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb10d655-e6c5-442d-99fc-a4ae530a4219/netgear_cg3000d_wireless_not_working.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/72669cd6-3332-4967-ae1d-1af9b7a31804/how_to_scan_a_document_from_hp_officejet_4500_to_computer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/08339087-7d87-4733-a12e-1703b29bfd7b/powenufijefit.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_off0000cdba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDBA 5892 bytes
SHA-256: e82808a63d9562e21dfbdb99edd0afd143fd26bfeec3ef6da8b2d6e0e409dfec
font_01_sfnt_off0000e1a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1A2 10976 bytes
SHA-256: d7c8af66364952de321ac394df5d6d41df7ffafd6d01aa65f9ac2e63d6641579