Malicious PDF — malware analysis report

Static analysis result for SHA-256 53b91bda8bf94521…

MALICIOUS

PDF

80.0 KB Created: 2021-05-04 04:03:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 0f2cec0a1643935a5868b1ef89f560d1 SHA-1: 548c38a5edf5c2a9e174e2a1be3785d1063735a6 SHA-256: 53b91bda8bf94521cafd78ad41158ee41c8cced273756bd159504419c218de73
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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://dugedepap.ru/strik?utm_term=ar+15+fixed+stock+magpul PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4450434/normal_60384b357eef0.pdfIn PDF document text
    • http://kitixukizogutik.mygamesonline.org/nukadojoridupizenaso.pdfIn PDF document text
    • http://jerimujolegem.medianewsonline.com/brs_biochemistry_mcqs.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393624/normal_60096c7226dc8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378157/normal_5fdc7d5a9e5a9.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4387589/normal_5fc5e9f9be5b6.pdfIn PDF document text
    • https://zavutotarewif.weebly.com/uploads/1/3/1/3/131379951/98186099f03.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376369/normal_601252e6e63ce.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411220/normal_601d3b21d9572.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489979/normal_60264468ed420.pdfIn PDF document text
    • http://nozumupi.medianewsonline.com/microsoft_certifications_roadmap_2020.pdfIn PDF document text
    • https://gazesomudari.weebly.com/uploads/1/3/1/0/131070071/bebidusofev.pdfIn PDF document text
    • http://delozofize.scienceontheweb.net/76101365021.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370768/normal_605257051dca0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381104/normal_606bab1ae5bbc.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/fb4bf2ee-2833-403a-8cff-5391a5fe6ec7/dugekabim.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e8889dc1-ebb6-45bc-8d89-618df7cb52bb/35411998361.pdfIn PDF document text
    • https://s3.amazonaws.com/jadudusujuje/bleacher_report_real_madrid_ajax.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4626d28c-c970-4fc9-b643-687c09b38093/zojipulixawofatuji.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0699d7d0-0dc7-4609-9b46-1b4988e2e0e7/1854598404.pdfIn PDF document text
    • https://s3.amazonaws.com/luropi/sazezawuwaterer.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_off0000f6ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6FF 5772 bytes
SHA-256: 38bf56fe80be9815eee1a52cbef227a2af0e13a205684c47dcce9f321369885b
font_01_sfnt_off00010aa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA9 11412 bytes
SHA-256: d0c88c738a20b541d4e45880f1a69c72a70256fb8fe8e3584a09c276d30a4713