Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac9cc8dc68c072f5…

MALICIOUS

PDF

75.2 KB Created: 2021-04-07 03:21:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: d55e9fe9e3ba0df5d7559b42ef0a67d0 SHA-1: e87b5b44914b64fc41c7e268868a1050626dc0ca SHA-256: ac9cc8dc68c072f5dfd2a6eb38d898bc37b5b61ac2721964fe811513ad1f62d3
126 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to disposable hosting services, indicating a link farm or SEO spam operation. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the presence of numerous external URLs suggests an attempt to redirect users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • 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.
  • 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://baarspo.ru/123?utm_term=capit%25C3%25A3es+da+areia+pdf+baixar PDF link annotation
    • https://cdn.sqhk.co/tarozawowe/jghh9ja/wifi_software_for_windows_7.pdfIn PDF document text
    • https://tejenopaje.weebly.com/uploads/1/3/1/1/131164027/4323344.pdfIn PDF document text
    • https://cdn.sqhk.co/gidetixi/deidHjc/mineral_oil_enema_for_dogs.pdfIn PDF document text
    • https://cdn.sqhk.co/tekunipifob/gfhbhdX/costumes_for_kids.pdfIn PDF document text
    • https://cdn.sqhk.co/dewozoju/gggghhY/neruxaludigifaw.pdfIn PDF document text
    • https://binapesod.weebly.com/uploads/1/3/1/4/131438069/safaxu.pdfIn PDF document text
    • https://cdn.sqhk.co/vopuvafamiw/hzjbYjg/jomubagotilif.pdfIn PDF document text
    • https://mujolimu.weebly.com/uploads/1/3/4/8/134868529/wumofiz_kaguposuf_lusumewevemeke_vezarubogapedov.pdfIn PDF document text
    • https://cdn.sqhk.co/lugizumevemu/jbje6Nk/among_us_free_game_on_chromebook.pdfIn PDF document text
    • https://cdn.sqhk.co/kezixowog/d0KKjhd/wedding_cake_edible_flower_decorations.pdfIn PDF document text
    • https://cdn.sqhk.co/vexapalas/geq5pxG/xafeb.pdfIn PDF document text
    • https://cdn.sqhk.co/zevijevam/PcgdkWD/fusoki.pdfIn PDF document text
    • https://cdn.sqhk.co/jarixizotib/ejNr6i3/tutobimisawabepovelob.pdfIn PDF document text
    • https://cdn.sqhk.co/kuwusemob/CtgeAkE/xujugu.pdfIn PDF document text
    • https://cdn.sqhk.co/sowodopevew/PfBjgLL/turbocharged_drift_trike.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://neveket.epizy.com/monuxazuduzunugijekunivo.pdfIn PDF document text
    • https://c6f55193-7475-4343-97dd-33cb3b141b6a.filesusr.com/ugd/808d8c_976fbdffb4db4b00be462428a1296f12.pdf?index=trueIn PDF document text
    • http://tirizalewofux.rf.gd/kusexujuxigokuloretux.pdfIn PDF document text
    • https://a815f367-2516-4b88-9496-eed07d5c1eb7.filesusr.com/ugd/665c20_1e9a459211064f07844505aea2bdf51d.pdf?index=trueIn PDF document text
    • https://9b56c271-8e60-4ff0-96d1-8930f8c082f8.filesusr.com/ugd/5a1ab0_ea81ed1375034a10b504f0c9aa061965.pdf?index=trueIn PDF document text
    • https://37bdae34-bb2f-403f-997c-54a7c09d9c06.filesusr.com/ugd/dc98cc_d6dff0a5b2be4cbdb22137fbc5807e0f.pdf?index=trueIn PDF document text
    • https://562a32fb-e9c8-4d8f-ac7e-a760da58c396.filesusr.com/ugd/68ec97_491ab79c22344cbfb69fc0771e8d5f6e.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e273.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE273 5436 bytes
SHA-256: a7976c34e13547158c1c3eef2099764c9af698b694e15f308efa31058f45bb8d
font_01_sfnt_off0000f461.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF461 13476 bytes
SHA-256: 93d227c9089144ac00b65f67e558b11326c35c4e36ddcc083bc5b57ecef8de4c