Malicious PDF — malware analysis report

Static analysis result for SHA-256 16b5bf129cb6554b…

MALICIOUS

PDF

77.3 KB Created: 2021-06-03 23:41:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 1c4bcb2e57e1c8937210b6268011f076 SHA-1: 4c4db142f4dcf1b7b4ec41a5faab8ce7eeb3a7d4 SHA-256: 16b5bf129cb6554bd9a5b7b32a94d9f3b1ef2c6ca7e2bdb6ed14f0e5b1294600
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are to other PDF documents, suggesting a link farm or SEO spam tactic. The ClamAV detection and ML classifier strongly indicate maliciousness, specifically identified as phishing. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a phishing lure designed to redirect users to malicious or spam content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 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.
  • 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://cructi.ru/pbw?utm_term=european+football+league+stats PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4449616/normal_606c4049e86b9.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4402503/normal_5ffed17d1ed21.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369330/normal_606ceff4c4ea3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409814/normal_60276a1e71cdc.pdfIn PDF document text
    • https://fakipaga.weebly.com/uploads/1/3/1/1/131163599/nijexelunazubuful.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393189/normal_60192a5b34a3a.pdfIn PDF document text
    • https://rujedupexiveviz.weebly.com/uploads/1/3/4/8/134874221/80b041407718271.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4504641/normal_5fe86918e29ec.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418401/normal_6065c33e12e76.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4528876/normal_5ff5a80571969.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450154/normal_60220b56cd8f0.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/e06685f7-f6b4-49b6-9e81-aae8c1e9ab4c/40594071680.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c22b7a33-9e53-410b-8fdc-cc902cae71ae/24152938293.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c84d9850-545c-411e-81c1-4630291b56a3/2967803916.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/199085ba-533c-4837-a01d-5db5a8933c08/lord_of_the_flies_summary_chapter_3-6.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c10b070-7a41-4cd5-80e3-c1bfe8879622/how_to_port_old_pc_games_to_android.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a64833b3-135c-46aa-b4c1-304a25c0151e/59749914585.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/42b104f0-2071-4542-871c-96ced4043358/49927791983.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ca61e4c7-b9f2-41e8-8e16-b9197d94c31c/fufujuvunukazewikage.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b7d782a-c2ed-4f12-8a7b-9307ca328eaf/lemebafadazuzimiranikutem.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d04e2ff6-a2c1-4bae-b5a0-7f46478eb15b/pathology_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/50f1b307-4258-4370-87be-c4c54d84096d/37999453252.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d480ac2a-ce69-4c80-8667-245cd319a8a3/the_poisoners_handbook_chapter_11_summary.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_off0000eeb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB2 5168 bytes
SHA-256: b6ca0f73c28d09d4156cb4e074a8862f39debad748fcc02ce91063a80b2ea1da
font_01_sfnt_off00010052.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10052 12592 bytes
SHA-256: 71cb9ad3f2140748e5238fcba80281ad77d142e6a3b62e7e86600bd87703e824