Malicious PDF — malware analysis report

Static analysis result for SHA-256 42c83a354015ed3f…

MALICIOUS

PDF

73.2 KB Created: 2021-05-25 08:35:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 508389bd763bcbb5bef2138e304fd2f3 SHA-1: 79cdc92bb2ed287cf5634df3b660a50d9ea4c09d SHA-256: 42c83a354015ed3fc2524010a8e891bf818174e37a05edaa0b0d3b73ac049494
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links, many pointing to disposable hosting services like Weebly, and is flagged as a link farm. ClamAV detected it as 'Pdf.Phishing.Trojan', and ML classifiers also flagged it as malicious. The presence of numerous external links suggests a potential distribution mechanism for further malicious content or phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • 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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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/strik?utm_term=aiou+degree+fee+challan PDF link annotation
    • https://kodetowunim.weebly.com/uploads/1/3/4/7/134701578/bbe89f76.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420924/normal_606c11f909a27.pdfIn PDF document text
    • https://wenuzivubog.weebly.com/uploads/1/3/5/3/135392435/gifiw_xiwegoronag_wenolobe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456996/normal_6026816e325fd.pdfIn PDF document text
    • https://nunesevafarub.weebly.com/uploads/1/3/0/8/130874378/wosidumunolawakox.pdfIn PDF document text
    • https://xunasumip.weebly.com/uploads/1/3/2/6/132696393/xiwikebuwet.pdfIn PDF document text
    • https://dezazobe.weebly.com/uploads/1/3/4/7/134755526/xexikugu-xowasokido.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417809/normal_60565dd0dadb3.pdfIn PDF document text
    • https://lovefuzabuzonif.weebly.com/uploads/1/3/4/1/134109130/zavene_xewob_noxuroka_wolokapun.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369794/normal_60029643f2aad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420260/normal_60317522c416c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451750/normal_601740202046f.pdfIn PDF document text
    • https://wikefazopikevi.weebly.com/uploads/1/3/4/7/134715570/gupebugokufiroxaxel.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/6ff6b35e-3d7a-4aa8-a3af-3d4fa32a637a/discografia_completa_daddy_yankee_mega.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/14824b2d-0469-4e2a-8e56-2481d62aba47/how_much_does_infinix_note_7_cost.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ab448760-ce5e-4136-995d-514a2868cc4f/virawexo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/610fa509-9cdf-49d0-afb4-b2a42ccd6760/47766207256.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b49c42ba-1bdc-4520-92cc-f77277078e0f/36443542276.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/787c9349-9e5d-4a48-abf5-bf981299d385/99981173431.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/982fffe7-50be-43c8-b8f1-b783be328b08/how_to_use_bella_mini_waffle_maker.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/34402811-e95b-4831-b2ee-d8989bc16ae9/dubudafetuxutu.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_off0000e27f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE27F 5096 bytes
SHA-256: 43bbbea0f04d64da05a9abfdb31c713b7c37e2c6a86bfbea2d214898f42f6a7b
font_01_sfnt_off0000f3d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D4 10416 bytes
SHA-256: dfe84796fbe4674ed0ef49d72663dc9dd17900c2f5f0e7afcca6a63612443dbc