Malicious PDF — malware analysis report

Static analysis result for SHA-256 771d5ef90f5ff5a4…

MALICIOUS

PDF

77.4 KB Created: 2021-03-11 19:09:33 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 95ad05a516b9452d122f753d7a9cb97b SHA-1: b42aa4660c3b877bcbcdef2e64d1cfef5f615aa2 SHA-256: 771d5ef90f5ff5a4f1cc58f26b3b53129d51781769b904206f1114edb1369814
126 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains numerous embedded URLs, with one specifically pointing to 'kuzutuzo.ru', suggesting it acts as a lure for phishing or to download further malicious content. The presence of multiple external URIs and link farm characteristics further supports its role as a distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kuzutuzo.ru/123?utm_term=fontana+lake+fishing+report+2018 PDF link annotation
    • https://cdn.sqhk.co/miwavilusaji/dicKjda/ice_cream_freezer_amazon.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422136/normal_60478a078d46b.pdfIn PDF document text
    • https://cdn.sqhk.co/bikakigiben/byM9Ddx/real_wrestling_3d_game_download_uptodown.pdfIn PDF document text
    • http://dizititakozazi.mywebcommunity.org/79976746420.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450870/normal_5fe81459e1689.pdfIn PDF document text
    • https://cdn.sqhk.co/regavebike/Piagigh/history_of_ancient_southern_africa.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4410004/normal_600490b40e90c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370762/normal_6013a3b1079ab.pdfIn PDF document text
    • http://geparup.scienceontheweb.net/77289287614.pdfIn PDF document text
    • https://cdn.sqhk.co/pewowutefiw/TifgXp2/decision_tree_template_google_docs.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482426/normal_6045eff610bc8.pdfIn PDF document text
    • https://cdn.sqhk.co/lubometusoz/jEpJOyD/fuxafuvaluxisefofamerasuk.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/adcd5231-8528-4b30-8720-1e83026df544/gamemaker_studio_2_download_cracked_2020.pdfIn PDF document text
    • http://dowuvoduwitovos.atwebpages.com/vomokomovesakasogojetof.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7d653630-02d9-4298-ba18-83fc57ac1cf4/wikokibidafuvavibokojedek.pdfIn PDF document text
    • https://edcb5511-827b-40b0-97c1-3499c313f96b.filesusr.com/ugd/0779a3_77091222f1224b948e1cea2dac26718b.pdf?index=trueIn PDF document text
    • https://ae8c1479-5121-4009-b0ed-8259dbb1205b.filesusr.com/ugd/0aff45_e43f9b8f9ac744c787d025d94dfe7538.pdf?index=trueIn PDF document text
    • http://rewuwuja.onlinewebshop.net/how_many_years_to_study_electrical_engineering_in_south_africa.pdfIn PDF document text
    • https://dbba0f06-1911-40f0-8c80-a2638c7f81cc.filesusr.com/ugd/b13fd1_825af030ea21424d8b06bf7cc98b9970.pdf?index=trueIn PDF document text
    • https://d54d55f4-8004-4613-9f19-7b96cbed0ae7.filesusr.com/ugd/ce4b32_4930b098c70c4bffa6a089cda3e16b63.pdf?index=trueIn PDF document text
    • https://7ef5d8b8-74ac-4e0a-b0a0-fa61ca6462a8.filesusr.com/ugd/23e9be_2bdb5c3a1e2d4e85842cbab273c221c6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/33b19abd-e082-4ac8-8ef6-a7b3a629acd5/xevoze.pdfIn PDF document text
    • https://53002a68-e35f-4167-ac88-1ab9777d7e72.filesusr.com/ugd/f5bc2a_46fb5ce6bb4743d09251189dd268b166.pdf?index=trueIn PDF document text
    • https://50037ee0-0691-4a53-bdc2-b2f8f795cfa6.filesusr.com/ugd/b41a9a_cd6311dc6dee48c188b627f931a0f676.pdf?index=trueIn PDF document text
    • http://zesafemumibow.myartsonline.com/rexab.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_off0000efef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFEF 5700 bytes
SHA-256: f54bc89e5d5f9eba12156e634b635ed6ef766ca4893d5206ec3e7a95fe67c930
font_01_sfnt_off00010360.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10360 10720 bytes
SHA-256: 504eefd0188b79913fd3cfaa31ca4e84f4f62a6834b7150c0d5ffc660f9097ff