Malicious PDF — malware analysis report

Static analysis result for SHA-256 0724aaaa0646f3b6…

MALICIOUS

PDF

83.8 KB Created: 2021-04-01 10:44:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: dca9ba7dad8f1e55df1eadd370991af5 SHA-1: 231611ec1de6e70de823f8d1ff5ba5ded4958856 SHA-256: 0724aaaa0646f3b66b510a9b82d2cadea1609682051e0f61f5faf5feb7ec6b02
184 Risk Score

Malware Insights

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

The PDF contains embedded links that redirect to malicious infrastructure, specifically identified by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The primary malicious URL, 'https://dafemum.ru/strik?utm_term=how+to+calibrate+samsung+galaxy+note+4+battery', is presented in a way that suggests it is a search result, likely to trick users into clicking. The ML classifier and ClamAV detection strongly indicate malicious intent, classifying it as a phishing or trojan PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/strik?utm_term=how+to+calibrate+samsung+galaxy+note+4+battery In PDF document text
    • http://teachost.com/what_are_the_4_basic_principles_of_the_declaration_of_independence57yrf.pdfIn PDF document text
    • http://zisuroto.mygamesonline.org/american_stories_a_history_of_the_united_states_volume_1_ebook.pdfIn PDF document text
    • http://selectgetc.top/953950553035dub3.pdfIn PDF document text
    • http://blankid.ru/batadilagesofukc7yj.pdfIn PDF document text
    • http://nibakelenixezas.getenjoyment.net/benedetto_croce_aesthetics.pdfIn PDF document text
    • http://picply.ru/tough_solar_g-shock_illuminator_watchr6y7t.pdfIn PDF document text
    • http://gepavozo.mygamesonline.org/36843049914.pdfIn PDF document text
    • http://zereteleriw.getenjoyment.net/relol.pdfIn PDF document text
    • http://nipamaton.22web.org/gozemerivuj.pdfIn PDF document text
    • http://hightrade.club/42299925214ygwbc.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://77a48bbd-706a-45f8-a225-ac1cc02029d7.filesusr.com/ugd/3be48b_c46a1235b4e2474dafacc0212e7626b9.pdf?index=trueIn PDF document text
    • https://99f4a897-b223-4833-863a-50ad465ba5d5.filesusr.com/ugd/8e2371_4173453748324879b3eeedf9fa0fec75.pdf?index=trueIn PDF document text
    • https://18e7ef82-5c75-44fe-ae22-4c356c2c9ce0.filesusr.com/ugd/749e61_ed3e07f4a80349fd8a0306fff37f24ae.pdf?index=trueIn PDF document text
    • https://315736c7-1030-4200-8d24-05c9f4951019.filesusr.com/ugd/d19ca0_e4dcac9364cf4dd29450d487b5b43f7c.pdf?index=trueIn PDF document text
    • https://67258aaf-84c5-4a88-bfd2-1aa7ddb6c27a.filesusr.com/ugd/850f07_37166507cb2a43b59cd9eb014143bf99.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/ratixifo/71643432459.pdfIn PDF document text
    • https://s3.amazonaws.com/makumapikeze/30826718330.pdfIn PDF document text
    • https://s3.amazonaws.com/jinabom/graco_nautilus_3-in-1_car_seat_put_back_together.pdfIn PDF document text
    • http://koraxirimaxodet.epizy.com/gaterexajarosalegatex.pdfIn PDF document text
    • http://kabumaja.rf.gd/xazedezorotazugapap.pdfIn PDF document text
    • http://katuribadelu.rf.gd/ruud_silhouette_filter_location.pdfIn PDF document text
    • https://s3.amazonaws.com/sewamos/38084908075.pdfIn PDF document text
    • http://baxojusijopigas.rf.gd/2684242680.pdfIn PDF document text
    • https://7c3a386c-9197-44ff-a2a0-26a6be1b6260.filesusr.com/ugd/bba797_da7c8d6b6933465d9827347f3b93db10.pdf?index=trueIn 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_off0000f84f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF84F 5452 bytes
SHA-256: f4c79dceb25387c4ecaa57feb55bfa9376516b98b5cb3cb6355f522cf36e7b0d
font_01_sfnt_off00010ada.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ADA 11364 bytes
SHA-256: bdbb6ca720a2796e0759f5a8454e755281e31028e9d1ce1c91683d9405e943c1
font_02_sfnt_off00013195.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13195 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3