Malicious PDF — malware analysis report

Static analysis result for SHA-256 334f5afe5a7dfde0…

MALICIOUS

PDF

116.5 KB Created: 2021-04-24 23:08:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-02
MD5: f6c36b328acf8b4417051dec3278e4ef SHA-1: e7b99657b770460905f08516075113836e08e488 SHA-256: 334f5afe5a7dfde04510818ae8f839b21746378285fc1e651a14b0db80848913
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of embedded links, many of which lead to disposable domains and known malicious redirectors. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, but the heuristic firings clearly point to a link farm designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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
  • 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 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.
  • 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://yafferge.ru/strik?utm_term=study+in+scarlet+quotes In PDF document text
    • http://latencfsrt.space/almanac_missouri_weather22squ.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480382/normal_606013527342d.pdfIn PDF document text
    • https://mozalotajevel.weebly.com/uploads/1/3/2/6/132682758/1a09d228194.pdfIn PDF document text
    • https://xotogifove.weebly.com/uploads/1/3/1/4/131406695/891840.pdfIn PDF document text
    • http://obmenkalnr.online/forecasting_techniques_in_human_resource_planningujmh4.pdfIn PDF document text
    • http://rekipeva.iblogger.org/xidudofuxuxur.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387229/normal_5fe8c578cf415.pdfIn PDF document text
    • http://help-violation.com/kindle_paperwhite_3_format_plikulwhza.pdfIn PDF document text
    • https://polokoxukoneg.weebly.com/uploads/1/3/2/8/132816042/1711278.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366316/normal_5ff97ab6e74b1.pdfIn PDF document text
    • http://kukikifo.iblogger.org/admiralty_law_books.pdfIn PDF document text
    • http://jushq.club/fisher_and_paykel_dishdrawer_recommended_detergent5bo67.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vifufabujeso.epizy.com/ejercicio_aerobio_y_anaerobio.pdfIn PDF document text
    • https://2bb9e989-9ce9-409f-aa8a-839f2ea8d3bf.filesusr.com/ugd/9f8cc2_9f8afe220fe647169d1d9fe92f749b79.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/2d440531-c974-4e0b-bc41-942343dbddb3/fujitsu_fi_7160_scanner_driver_for_mac.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/30160209-a53a-4675-8a3c-64283908de32/how_to_stop_climate_change_essay.pdfIn PDF document text
    • https://05282879-aed3-4f16-ac14-d534add4d4bd.filesusr.com/ugd/0f8b7c_14bce1b8744149cb8c682eba4637d080.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/62b7c171-ad8e-464c-829a-8d01d0ed2b97/6320807897.pdfIn PDF document text
    • https://0a37a3d5-a0bf-4e77-8ff5-6127fd08aefa.filesusr.com/ugd/6046c9_001baac1e969410292eebde99aaab81e.pdf?index=trueIn PDF document text
    • http://zapofekeba.rf.gd/what_is_aeries_student_information_system.pdfIn PDF document text
    • http://mutupoda.rf.gd/argala_stotram_in_english.pdfIn PDF document text
    • https://c6f55193-7475-4343-97dd-33cb3b141b6a.filesusr.com/ugd/808d8c_f363d2cb4c4f4501b2c14d2bacbbc31d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/dba2e08f-bbbe-466a-b765-a96208e711bf/can_you_day_trade_on_trading_212_isa.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_off00018ddf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18DDF 5264 bytes
SHA-256: a0696473b0f888b289f0bf5187538f224f458921c05f1259f6d9e15ce76e1b99
font_01_sfnt_off00019fd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19FD8 10628 bytes
SHA-256: 82890e0a1304da3d05a877600e0621b46bda5b25b9f148d87a075884ffa93f7f