Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac91058b15f4242b…

MALICIOUS

PDF

71.2 KB Created: 2020-11-24 01:47:09 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 5c2398d0dad348d80c8e62bb3eba9585 SHA-1: 99fe9ca4bf696d775741940e5409f8b5db079e49 SHA-256: ac91058b15f4242b822cdf7289779212a68fb2e2a81cea109a557be0ae36ac8c
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-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.
  • 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://trafffe.ru/strik?utm_term=3ds+emulator+online PDF link annotation
    • https://xelegiri.weebly.com/uploads/1/3/4/4/134435730/8976104.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383475/normal_5fa8ca42e433d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367289/normal_5fb7597aeb058.pdfIn PDF document text
    • https://gobumireg.weebly.com/uploads/1/3/1/3/131383916/952cbe9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408478/normal_5fa614828b74c.pdfIn PDF document text
    • https://nuvetifozeg.weebly.com/uploads/1/3/4/3/134358797/6253473.pdfIn PDF document text
    • https://dudabiwik.weebly.com/uploads/1/3/4/3/134354119/xilodaledige.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478683/normal_5fa90ba493b11.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443362/normal_5faf89a2c8cbc.pdfIn PDF document text
    • https://ditiwudo.weebly.com/uploads/1/3/1/4/131452947/xokobew_mavefubowubijus_rebuniwumawanom_vufisojufekaj.pdfIn PDF document text
    • https://wipomozexabezi.weebly.com/uploads/1/3/0/7/130776841/3063586.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383802/normal_5fa2efa12c9f0.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/3e7148a6-e587-4e55-bc5e-80c9c7f95c7e/butterfly_short_story_in_english.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_off0000da19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA19 5040 bytes
SHA-256: c53016d2ae57536a85805a064befa4ddc1734fe6bf6b02a6afbc5a624c067522
font_01_sfnt_off0000eb1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB1C 10824 bytes
SHA-256: 68d3e4ea5b70c8d61a5c0fde21941aaad596f1bd5e063b682d2a4411715ea8a0