Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcb86e7d13ba72c1…

MALICIOUS

PDF

80.8 KB Created: 2021-03-25 15:27:34 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 7e17dff45ec957bf03df14d83c30fad5 SHA-1: 5756f88ce6638250fd9ce5656e3e5020fe4a2fc1 SHA-256: bcb86e7d13ba72c1a3e707db210d540894871cc312cb1be19dd2f56cc427a914
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by 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 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://gimoguvi.ru/strik?utm_term=navy+seal+museum+fort+pierce+fl PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4473023/normal_601e6578547e3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4405925/normal_5ff6c4dc97b4e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382627/normal_60172c2585a79.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424696/normal_600c73d2c3b6b.pdfIn PDF document text
    • http://zomosidotewe.sportsontheweb.net/cbt_for_adolescent_depression.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368735/normal_5fd9820771328.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://3d5b2cfc-74f5-4c02-8466-0d369b02955c.filesusr.com/ugd/69b86f_8143da74a1514ec085c20e5053660d7c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/8e82440a-8eda-4d76-852d-2dda122c1d95/19756561172.pdfIn PDF document text
    • https://c0a42e0f-4cce-4e1b-84a6-2a5440198d67.filesusr.com/ugd/440b6d_b99a86d804b8424996b11a91c7e19286.pdf?index=trueIn PDF document text
    • http://litorow.myartsonline.com/zevuwasosusofuvo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9ea843de-2cce-4025-924a-a10eb7967999/39705423220.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5b302221-10e4-4cf7-afc5-292089466deb/craftsman_3_gallon_air_compressor_replacement_parts.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/df2c2682-11e5-4f7e-a841-c49d237c3f89/99517902184.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d1cc11aa-2bcd-4dd2-8df5-291b144c0594/tetatuvanejogositerivuxil.pdfIn PDF document text
    • https://s3.amazonaws.com/lazolu/lozilanul.pdfIn PDF document text
    • http://rugoxesoteko.myartsonline.com/37143964102.pdfIn PDF document text
    • https://s3.amazonaws.com/rekawexuretowo/komejugujugigekobojaxo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/730d36ae-12d8-44be-8997-2b0aaa8c6781/17695670935.pdfIn PDF document text
    • https://a2876ee3-c470-454a-91e2-e108d831033a.filesusr.com/ugd/e8dba5_2dfe3e6554cf4eb48ee6912998090022.pdf?index=trueIn PDF document text
    • https://ebcfae26-b4e4-4f1a-a5b2-c5bdbddc1bdf.filesusr.com/ugd/259f90_5b06e403c384467598ff6e9ea119ab1d.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f106.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF106 5068 bytes
SHA-256: 19f98bfa7beff2f27e0a6ce18fe55da58ae80aa14fa670996fead3809bbd50eb
font_01_sfnt_off00010264.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10264 10980 bytes
SHA-256: a48b2e140cedbe464fc0b91aab8e69493d6dabf0d8e3de613951565d2fb46d73
font_02_sfnt_off000127cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127CF 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333