Malicious PDF — malware analysis report

Static analysis result for SHA-256 c66c5a5771b17b59…

MALICIOUS

PDF

70.6 KB Created: 2021-04-04 13:09:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 85cd1f0731328ca5dfd69001e248e249 SHA-1: 857f7da5176d83eafce1a58352e7265481fd4b0f SHA-256: c66c5a5771b17b592c427d0b7038ec4e1d6f0a6c25073b04fe7efcc679a71c63
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 0.9998

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://zajinet.ru/wix?keyword=biba+model+no+read+down PDF link annotation
    • http://libopadu.scienceontheweb.net/sabikeditipefipaturu.pdfIn PDF document text
    • https://nevofegef.weebly.com/uploads/1/3/4/8/134851200/kubekiwereba_kisovikok.pdfIn PDF document text
    • https://vipukawolatu.weebly.com/uploads/1/3/4/4/134486161/zirunetavetoku.pdfIn PDF document text
    • https://kezidixujaroko.weebly.com/uploads/1/3/4/0/134040737/1754288.pdfIn PDF document text
    • https://wodirukuz.weebly.com/uploads/1/3/5/3/135398055/vawarepilulafa.pdfIn PDF document text
    • http://nigavereke.mygamesonline.org/capitulo_baleia_vidas_secas.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/fatisake/75769513946.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6af505c-fde7-4730-8b35-3f97de0324e2/what_are_the_first_20_elements_in_order.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ce9f471e-5160-4701-ae50-bcd508949b96/prayers_that_avail_much_health_and_healing.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/22f85e9b-abff-42a4-b0d7-a8d5978c77d7/how_to_use_an_all_american_pressure_cooker.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3011c495-0d5d-43e5-833e-a4aed3cf0784/roles_and_responsibilities_of_operations_manager_in_construction.pdfIn PDF document text
    • https://s3.amazonaws.com/gowupuzokowuxes/abcd_2_movie_all_ringtone.pdfIn PDF document text
    • http://zorufuzelal.rf.gd/naredufogivudomidi.pdfIn PDF document text
    • http://fedonefekipide.myartsonline.com/dieta_astringente_pediatrica.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/00b3e07b-7e18-4da8-8a90-39158672a7c9/using_mpc_essentials_in_pro_tools.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/70042f05-a732-43b3-9c21-baf394de4347/advanced_financial_modelling_in_excel.pdfIn PDF document text
    • http://mojebevusawibo.rf.gd/werani.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/824b9145-507a-484a-94ee-a43b7da2e606/minuet_in_g_major_anna_magdalena_bach.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/90197328-b2eb-44db-b2a6-eeb1e6d086b1/9542228006.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1410c615-123a-4466-aacf-b1cbb117dd9d/62078251580.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_off0000d8c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C9 5072 bytes
SHA-256: c14cca178cbacfbae1d32a1cc27353c9174449eb93d830866f887924c077d4b6
font_01_sfnt_off0000e9fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9FD 10244 bytes
SHA-256: 53166d40dff21a3b35e16f29870a823c0c4acff17eb7eb4dd230688b9b9cdaa7