Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a76db3c25c85c67…

MALICIOUS

PDF

53.5 KB Created: 2020-10-18 08:31:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 583d419f424f1c37e50e321f96ae409a SHA-1: 905ecf37835d7ebe6a1a3e9906e46bc5136be4ce SHA-256: 8a76db3c25c85c679142c047e8decc1c7c2eab0339ba27a931b4a3b77e84b717
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many pointing to external PDF files, suggesting a link farm or SEO poisoning tactic. One prominent URL, 'https://cctraff.ru/strik?keyword=entrevista+periodistica+ejemplo+corta', is identified as a malicious redirector. The document body, though heavily obfuscated, contains this URL and appears to be a lure related to a journalistic interview. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://cctraff.ru/strik?keyword=entrevista+periodistica+ejemplo+corta In PDF document text
    • https://cdn-cms.f-static.net/uploads/4367271/normal_5f88f730694bd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374839/normal_5f8a583654022.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365653/normal_5f8711afeb7a0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365636/normal_5f8b4a9225a91.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369905/normal_5f8b68373ef3a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366389/normal_5f8bd163ac956.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367287/normal_5f8762eb75ad5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370053/normal_5f8a650ccd373.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367271/normal_5f8b9237d4d7f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367665/normal_5f8758eb1c994.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366660/normal_5f87a47e3cf7d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372723/normal_5f8b80fe71da0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368224/normal_5f880bafec279.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366041/normal_5f8b7d0019fb6.pdfIn PDF document text
    • https://dumitekajeru.weebly.com/uploads/1/3/0/7/130740207/seditazubuk.pdfIn PDF document text
    • https://nipaxibovaj.weebly.com/uploads/1/3/1/3/131379211/8121474.pdfIn PDF document text
    • https://ganulexotugoris.weebly.com/uploads/1/3/1/1/131164012/sosef.pdfIn PDF document text
    • https://godadonalizubo.weebly.com/uploads/1/3/1/4/131437317/6567886.pdfIn PDF document text
    • https://babinekisifuve.weebly.com/uploads/1/3/2/6/132696104/pokixufiruzok.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366385/normal_5f873f6aa5cfc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371800/normal_5f8a7f2d28e59.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371261/normal_5f8b3d6529d82.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379854/normal_5f8a91e3f18db.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/2a50a6b3-3a4a-41c8-a762-17f7899d2799/suxalabenoxuvi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3a9cd845-d49f-4cba-a426-5b4a5563b071/64506685987.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/482dd362-6580-4c37-9163-c4dfe82e19c0/posugudo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/075d10ac-294c-48e6-a218-06b0ac7b4487/58412541619.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000826d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x826D 5100 bytes
SHA-256: 4033c85f662ac854d0372a3f444f8e911216bd3b668b638a9fc042a3ce9dddaa
font_01_sfnt_off000093ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x93AE 11216 bytes
SHA-256: 5dcfbb63956bbcfb81ad1a156999a3b8b4373085f8a6080447328a5f17a1eb7c
font_02_sfnt_off0000b80e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB80E 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c