Malicious PDF — malware analysis report

Static analysis result for SHA-256 27b329233f09db6a…

MALICIOUS

PDF

94.2 KB Created: 2021-05-28 20:45:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 6645daa10aa6d9bc13ca87e78797cf4b SHA-1: 50d19d8770454f98b523f4f5ec646afbb21a0e47 SHA-256: 27b329233f09db6a40900564254dacc41b63f2f3a2dd509874a40b003c1c0887
186 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a significant number of external links, many pointing to disposable hosting, indicating a link farm designed to distribute malicious content. The presence of numerous external links suggests an attempt to lure users to external sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://nipisod.ru/123?utm_term=busqueda+de+voz+apk PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4387577/normal_5ff5a3980780f.pdfIn PDF document text
    • https://wevapagavum.weebly.com/uploads/1/3/4/3/134306171/1518780.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4402014/normal_60b05e9b1de9d.pdfIn PDF document text
    • https://vukijimox.weebly.com/uploads/1/3/4/3/134358494/debujixugovizo.pdfIn PDF document text
    • https://jevizaja.weebly.com/uploads/1/3/4/8/134869407/fd748d1bc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379387/normal_60595f32a0830.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449185/normal_604e77c57d9ae.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474978/normal_6015c619a488d.pdfIn PDF document text
    • https://funovupudejo.weebly.com/uploads/1/3/4/4/134473131/751136.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/3b93c8bf-2f07-4e0e-9700-6dc0a96b4eb7/twilight_google_docs_mp4.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a7c592c9-d36c-48db-83e1-a3c989a0ec4d/what_is_the_difference_between_capital_expenditure_and_deferred_revenue_expenditure.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ca6e025-902b-4edb-8a47-44d42b160198/28228498809.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eef96098-80df-4111-9fc7-f41ce19dc1b2/xoxawomu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f9a66ed3-87fa-4ad4-ae19-33f101165245/jalefosubonatamufasi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/91453226-08ff-4c01-8032-0032db95a787/the_dark_elf_trilogy.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9bc24655-ece3-4680-b4da-022d4f462fc0/what_is_matrix_organizational_structure_example.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/065679bd-62a4-41e7-8855-00904a0db2b9/conjugacion_de_verbos_regulares_e_irregulares_en_espaol.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/81aad401-d2bb-49a7-acb8-47eb406b97c9/65405322811.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011a0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A0F 5176 bytes
SHA-256: 9c40d3ec7f6d3a84a7a0fc34d1fc98a96acff3fb9baf01ed85b036429cb8dc38
font_01_sfnt_off00012bc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BC6 5908 bytes
SHA-256: 10d158472a0c990aa3b1f44cf4a76f2ea61483844c8a2d971eae406145ade697
font_02_sfnt_off00013fee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FEE 12876 bytes
SHA-256: ab53e1fa2e98b0fb0d4a63780a7077606395f8fe1adeb498ecb8e08fc8104dfe