Malicious PDF — malware analysis report

Static analysis result for SHA-256 6531c36a1ff6a5dc…

MALICIOUS

PDF

70.7 KB Created: 2021-04-07 12:39:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 9d2fb1b76537944a36ad56fadf4459ec SHA-1: 51839fa0288c51298d347c63ee79b5d66f3addec SHA-256: 6531c36a1ff6a5dcf080acd1b6b8c15953600110c6f4ac5b27117fb4f095bd61
126 Risk Score

Malware Insights

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

The PDF contains numerous external links, with one prominent URL pointing to a suspicious domain, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly indicate maliciousness, classifying it as Pdf.Phishing.Trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this by identifying the PDF as a link farm on disposable hosting, likely to obscure the true destination. No scripts were extracted, but the embedded URLs are the primary indicators of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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://jottigo.ru/123?utm_term=datasheet+thyristor+bt151 PDF link annotation
    • https://cdn.sqhk.co/pemejurove/6nhjhgg/objective_zoology.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447646/normal_60598564c060b.pdfIn PDF document text
    • https://cdn.sqhk.co/tevunufoba/jawhivv/hello_neighbor_red_key_room_act_2.pdfIn PDF document text
    • https://cdn.sqhk.co/wikelere/hhvjcHt/45082814369.pdfIn PDF document text
    • https://cdn.sqhk.co/vobevufubito/ihhhhpF/push_and_pop_vector_c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415951/normal_602111741d395.pdfIn PDF document text
    • http://lovupijuti.getenjoyment.net/vavabivujatoluratosibi.pdfIn PDF document text
    • https://cdn.sqhk.co/jodolupuvit/ghidjaJ/strucid_battle_royale_roblox.pdfIn PDF document text
    • http://xibomupazone.mypressonline.com/84265887919.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443624/normal_5fd2f880dfb61.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485929/normal_60153452ecf5a.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/3274dcfd-8a34-4402-95be-e5dadba37509/zamuzufojixalupumitube.pdfIn PDF document text
    • https://s3.amazonaws.com/zubuwujoxom/osha_regulations_for_building_construction.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f9a48d2e-7431-410a-84b1-f8b9c9e35835/fetaxuwiniwepewasamikome.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ada1d183-82dc-452c-ac95-d9b87b29cb01/what_are_the_7_prayers_of_daniel.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/61107e29-8bae-48be-9f7e-93b1ba621110/mowamole.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1d2c9dd4-1646-4510-b7c5-e2f7998a6b2d/the_crown_season_2_episode_5_cast_list.pdfIn PDF document text
    • http://supajiwa.myartsonline.com/48921506996.pdfIn PDF document text
    • http://newemepakirid.myartsonline.com/kerudalalilafitamoz.pdfIn PDF document text
    • https://s3.amazonaws.com/sorogamat/saeco_odea_giro_descaling_solution.pdfIn PDF document text
    • https://s3.amazonaws.com/bifadiwuwileji/debijupogux.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_off0000d5c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C0 5160 bytes
SHA-256: 77ee3eb83ac0ca15695994b1f4829c3831f65d18ef372df9ee2c868610545ca8
font_01_sfnt_off0000e75c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE75C 10820 bytes
SHA-256: f44f4d3539d8acb1f6eae157b77e7850f7324881f9986687719ad3cab1410807