Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4e1b0c64d9815cd…

MALICIOUS

PDF

68.5 KB Created: 2021-03-24 19:57:16 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: a6dfc3db23b3faf3517041b21f573354 SHA-1: d7c1539bb45e6845709c32bebad4c5e31cde4a80 SHA-256: f4e1b0c64d9815cd594953f1715b364a5d8c2503ee965efdabcefe2f32327437
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains a large number of external links, a common technique for SEO manipulation or distributing malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and numerous external links suggest it may be used to redirect users to sites hosting exploits or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://baarspo.ru/award?keyword=classroom+rules+for+high+school+pdf PDF link annotation
    • https://cdn.sqhk.co/kelopifagisu/hjjjibl/faxenixigeni.pdfIn PDF document text
    • https://cdn.sqhk.co/vexorikodo/C6lKhf4/history_of_bookkeeping_in_nigeria.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369776/normal_604d1c135a1e6.pdfIn PDF document text
    • https://rilewinip.weebly.com/uploads/1/3/5/9/135964764/1080090.pdfIn PDF document text
    • https://datuzela.weebly.com/uploads/1/3/4/1/134109276/6841516.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4446270/normal_60086bf5059a1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4493891/normal_602c5d3a9eb9e.pdfIn PDF document text
    • https://totidulabi.weebly.com/uploads/1/3/1/6/131606487/9e29acb8053.pdfIn PDF document text
    • https://totidulabi.weebly.com/uploads/1/3/1/6/131606487/a47873.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489734/normal_605145f5463bb.pdfIn PDF document text
    • https://mujabimebedegi.weebly.com/uploads/1/3/4/2/134234846/bd9f0f2.pdfIn PDF document text
    • https://rinulokol.weebly.com/uploads/1/3/4/8/134868038/bowufapufa.pdfIn PDF document text
    • https://denutuzuno.weebly.com/uploads/1/3/4/7/134706868/zusoxajalibub_xipis_dalalu.pdfIn PDF document text
    • https://pebifabo.weebly.com/uploads/1/3/4/8/134892867/d52a7.pdfIn PDF document text
    • https://kajavowonedefa.weebly.com/uploads/1/3/4/8/134858644/bilidosopuv-lufila-subumineluz.pdfIn PDF document text
    • https://cdn.sqhk.co/zenujulikik/Uhchdgf/hockey_stars_game_unblocked.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475852/normal_604470f2c3f21.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458840/normal_605808eaa1762.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://sobogewas.epizy.com/camera_ai_vector_free.pdfIn PDF document text
    • http://wazewatiduxuz.epizy.com/76579923363.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_off0000cffe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFFE 5476 bytes
SHA-256: 7cd6df855f5658252fc73722f76c633edff15fdb766980ea7f52713237479db7
font_01_sfnt_off0000e26e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE26E 10140 bytes
SHA-256: 05f0eb5fff3f3e3d26a91029f8fdd35ddc0eabee0ace40ab0fac49e7f1825caa