Malicious PDF — malware analysis report

Static analysis result for SHA-256 b379c16d2ba8cc78…

MALICIOUS

PDF

75.4 KB Created: 2021-05-29 12:34:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 640deae0713e8973796b3831b44b1232 SHA-1: 5900acea5d0be91cd6bd921e5b9f82807fff3eed SHA-256: b379c16d2ba8cc7820895a5b3bcf574e0a4351a7a9fac7e04b8a443dd51d0d20
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

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/strik?utm_term=how+to+play+minecraft+pe+online+for+free PDF link annotation
    • https://xusalifur.weebly.com/uploads/1/3/4/1/134131705/kusumotamulisig-towejapijez-fidiwaso.pdfIn PDF document text
    • https://padefogufagabak.weebly.com/uploads/1/3/4/7/134714354/3054769.pdfIn PDF document text
    • https://direwuberegenis.weebly.com/uploads/1/3/4/3/134361890/8168474.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490720/normal_604931a36f4ee.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380694/normal_602c3019acd6e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375196/normal_601b9e6186e32.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426942/normal_600db17b82bb5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4444622/normal_5ff831ef36bf4.pdfIn PDF document text
    • https://gufurokis.weebly.com/uploads/1/3/1/4/131453316/8504179.pdfIn PDF document text
    • https://waluxine.weebly.com/uploads/1/3/4/7/134759732/xorizukixenerifujap.pdfIn PDF document text
    • https://sekotujuf.weebly.com/uploads/1/3/5/9/135960234/4c72d923ab2dcb.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/b60455fe-496f-47b6-81b3-aef647a63bc3/how_to_reset_samsung_refrigerator_error_code_8e.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0108b550-a6ec-486f-b7b0-e511024eef60/72583947478.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/17e5a4e9-a894-4dab-91d3-26c78558add5/harry_potter_free_printable_activities.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cfe2d8d0-2b05-4750-a91c-acf2c25b530d/40453314275.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/10535139-6cbb-4ee5-9bc3-efdee17a9711/narrative_essay_topics_for_6th_grade.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7d7fcf95-5118-4c47-b319-ee1e48c6a96c/gta_san_andreas_turkey_mod_final_kurulumu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/25bfd210-961c-4c34-9431-049d3738e4e4/will_ps5_have_exclusive_games.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8a90aa2c-fe67-4a72-889b-db93a2b0d92a/how_to_pair_a_dell_wireless_mouse.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9a6d9409-f07b-4d42-a419-12cb77d32fb5/42472609477.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5a7794dd-c3a4-4c39-b020-72f511d4d38b/galezixejexiluvaxe.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_off0000ebaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBAA 5136 bytes
SHA-256: f1fd085d3e4fb29c51c612caa1758d4b44c218e4ffaeb83b00f08c65a1c0903b
font_01_sfnt_off0000fd28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD28 10256 bytes
SHA-256: bcabf90c1bec492b1bbecac6aeca8c83bc18be969eac82bf256b8fbbb2e853f4