Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1ed6953b754bdbd…

MALICIOUS

PDF

101.1 KB Created: 2021-06-06 01:07:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: c289e80cbad0575febf5443f239f7a97 SHA-1: 552555181655c6d635d934187885a7bdfe9027d6 SHA-256: a1ed6953b754bdbd3edf20777320d8a347a1da60b9593ef0d480afb610fbb959
126 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO manipulation tactic. The ML classifier strongly indicates maliciousness. The embedded URLs likely lead to malicious content or phishing pages, and the document's structure suggests it's designed to drive traffic to these external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://pelibifir.ru/123?utm_term=subtracting+common+denominator+fraction+worksheets PDF link annotation
    • https://xoxomedeze.weebly.com/uploads/1/3/5/3/135308121/3336305.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389097/normal_602fba683e8a6.pdfIn PDF document text
    • https://kojovade.weebly.com/uploads/1/3/4/6/134681743/3503556.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490123/normal_603f3df172654.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4462344/normal_60b2ca02a122c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450513/normal_606e77c29448e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448985/normal_602387688b2b0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4367940/normal_5fcaa99abc308.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452376/normal_60445d064f120.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465538/normal_602fccde316f6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389106/normal_60324847ec479.pdfIn PDF document text
    • https://serivuzoforin.weebly.com/uploads/1/3/4/3/134334639/pugozolobem_watewuna_sunokizimolol.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479224/normal_601980a7ec2a4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366337/normal_6044d0a3d2ba9.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://mifimoruzuwo.pbworks.com/f/how_to_work_lyft_driver_app.pdfIn PDF document text
    • http://zosajivapesi.pbworks.com/w/file/fetch/144556032/27755636480.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3cc23261-6ea2-4ee2-90de-2e8a091eca34/free_nanda_nursing_diagnosis_2018.pdfIn PDF document text
    • http://sovafiben.pbworks.com/w/file/fetch/144620523/data_entry_operator_course_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8e3f5c24-a449-4c1a-855f-9a3295373683/23491014641.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013883.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13883 5804 bytes
SHA-256: c1ce74121b6d7ad466a4d01abca0c8da4162c0b30cebf157bde0f1c94ff9baa5
font_01_sfnt_off00014c2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C2B 10544 bytes
SHA-256: 503d2bb27b92b290ca293fc51fb1ec089ff0d892eeac5f3b393a5ced0a175f31
font_02_sfnt_off00017078.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17078 16176 bytes
SHA-256: 8571c69df712043f52364268a050b27bc1059f3809e3f2b49cbb8768f33e3ff2