Malicious PDF — malware analysis report

Static analysis result for SHA-256 b575feb377f68154…

MALICIOUS

PDF

70.4 KB Created: 2021-03-29 18:45:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 22fbceef845254b1ddc23050af2e955b SHA-1: c57046055069281d88b363dedb8f73e8eb275507 SHA-256: b575feb377f6815476747fc9d279e92f0ff19874b070d8ef34fe28deb6f13b5d
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm, with a high ML score and ClamAV detection indicating malicious intent. It contains numerous external links, including one to 'kuzutuzo.ru', suggesting it is designed to redirect users to potentially harmful websites. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure points to SEO manipulation or phishing tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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://kuzutuzo.ru/wix?keyword=bemis+humidifier+filters+1043 PDF link annotation
    • https://cdn.sqhk.co/luwesefizi/gUVjjhe/x_shot_crusher_amazon.pdfIn PDF document text
    • https://cdn.sqhk.co/rowubuvuke/fmlejgj/bullet_echo_hack_android.pdfIn PDF document text
    • https://cdn.sqhk.co/mozedizupi/3jfrjhE/classifying_numbers_worksheet.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4409799/normal_5fe0674d91dda.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415754/normal_604b9f23e9cc7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403131/normal_5fe942ff38450.pdfIn PDF document text
    • https://cdn.sqhk.co/kitujesijak/jggjcvE/51750948273.pdfIn PDF document text
    • https://cdn.sqhk.co/jawakagufu/ieidyCW/alivio_medical_center_morgan_fax_number.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466173/normal_60491a2441813.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480414/normal_5fe276a73e324.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/3c0fc658-874b-401a-8508-92cab7d93eff/how_to_reset_a_viper_alarm.pdfIn PDF document text
    • http://kanisal.epizy.com/porter_cable_finish_nail_gun_repair.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/af7e023f-f300-4f18-ae63-71796f7eb1ea/does_cyberpunk_2077_run_well_on_xbox_one_s.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/516e58df-8af2-4dad-a045-66d528742edd/sketchup_make_2017_license_free.pdfIn PDF document text
    • https://fe426b01-1dd0-498a-b08e-7ec37e320b94.filesusr.com/ugd/6b45f0_b44098dcdbd345059dea51b2b343307d.pdf?index=trueIn PDF document text
    • http://tapopopabe.rf.gd/audio_editor_free_softonic.pdfIn PDF document text
    • https://b81e1767-bb0d-4562-9f98-cfef66859bb1.filesusr.com/ugd/b48b60_65827af2bd15475696bc6673dcfaa1f4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/fa24cf06-e02e-45a7-9125-8aad0bfacf58/43266388248.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/81ff6e5c-e8eb-4283-9bb0-ef060f3da654/zoruv.pdfIn PDF document text
    • https://40e214c1-1950-44e8-a195-e2c6eeb23253.filesusr.com/ugd/a517f4_6aad5f533eb14839afca7d924f5feaaa.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1a743201-0877-4aca-ac02-6442f129caa4/98319518184.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_off0000d5ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5AD 5432 bytes
SHA-256: 9acab8970be18e1ef96fc9a159e93f62cb558be4355f58113fdbdbcdd76a17cf
font_01_sfnt_off0000e808.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE808 10760 bytes
SHA-256: 2c5915606773e00e36d5315e6c50537cd3ede48d7f84e0b80a965e7b4314fa5f