Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb794d10be30ddf5…

MALICIOUS

PDF

73.1 KB Created: 2021-05-14 07:52:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 392605bd86ff88f514fea5d987d33322 SHA-1: 7b5cc6387130a0d6657e05a02604048ef252a8bc SHA-256: cb794d10be30ddf56480a933714ea59dca3829a7499ff360e5117ddc5cdcccda
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous external URLs, with one notable URL being https://druttle.ru/strik?utm_term=how+often+should+you+change+oil+in+a+diesel+generator. The presence of a link farm suggests the document is likely used for SEO manipulation or to host phishing lures, aligning with the Spearphishing Attachment technique.

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://druttle.ru/strik?utm_term=how+often+should+you+change+oil+in+a+diesel+generator PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4486045/normal_605a0bde8507e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379731/normal_60065a6c7193d.pdfIn PDF document text
    • http://tetoxukipim.getenjoyment.net/sheet_bending_machine_manual.pdfIn PDF document text
    • https://sokevabo.weebly.com/uploads/1/3/4/6/134665749/46437.pdfIn PDF document text
    • http://dupamineni.medianewsonline.com/spiral_bevel_gear_calculation.pdfIn PDF document text
    • https://nirejabepifu.weebly.com/uploads/1/3/4/2/134266024/savanalorapop_witizazuxonopug.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/3ac15526-5197-4823-bf14-c202b6d35305/write_list_to_text_file_python_3.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4d89b037-5170-43b7-a582-1b70ae54080a/53789880771.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/68a1d886-6e20-4d62-828a-787558b3e6e1/37277218455.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6502aa10-a9d3-495d-b6de-bf836e89a2de/z-line_designs_fiore_tv_stand_with_integrated_mount_for_tvs.pdfIn PDF document text
    • https://s3.amazonaws.com/ruzaganog/casual_leave_application_format_for_office.pdfIn PDF document text
    • https://s3.amazonaws.com/fewifuwu/10894396700.pdfIn PDF document text
    • https://s3.amazonaws.com/ganubifirigevi/zexevumelubapaton.pdfIn PDF document text
    • https://s3.amazonaws.com/jubiferekaka/artbat_upperground_original_mix.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7da839e9-0725-4f50-87a9-fa3ffa846dae/gumomebus.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/92751684-be97-4f12-8922-1ed11d8223e0/what_do_pecha_kucha_mean.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ee157915-7485-4fd1-a832-2a6e1146daba/66564304727.pdfIn PDF document text
    • https://s3.amazonaws.com/lizuseguwix/kgf_audio_songs_free_in_tamil.pdfIn PDF document text
    • http://neketepa.myartsonline.com/merge_pdfs_function_in_r.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b5522489-62d6-4f6c-8350-8af18234ea5f/51922830996.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_off0000e0c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C9 5436 bytes
SHA-256: 7c19be1f78d32740d42ff87499b5a7c596b46e5669e62ec4b6c306968eb08f49
font_01_sfnt_off0000f361.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF361 10436 bytes
SHA-256: 4689eadc67a95e338a48f1d8a588022b0ff1867f110d46742eeb0ad36d76df48