Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d17856005edd480…

MALICIOUS

PDF

78.8 KB Created: 2021-05-25 17:09:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: 52c3c7e5da2f8d7dfd6eec380b64f513 SHA-1: 1a4c31246f1b65e10725098112c89636b2e88098 SHA-256: 6d17856005edd48080f408fc5374fea7e5c9887041a3553e0f4369000b2db8f2
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of techniques used to redirect users to malicious 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://seumenha.ru/strik?utm_term=financial+accounting+quiz+questions+and+answers+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4375694/normal_5fe7d1e1f1632.pdfIn PDF document text
    • https://gajodiwu.weebly.com/uploads/1/3/4/0/134042407/1180216.pdfIn PDF document text
    • https://xukoperupe.weebly.com/uploads/1/3/4/7/134743664/4109260.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454971/normal_601a2a53a06d7.pdfIn PDF document text
    • https://nunevebola.weebly.com/uploads/1/3/4/8/134846747/9b57704e4519.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489237/normal_6044f5670b706.pdfIn PDF document text
    • https://nogomikosisodop.weebly.com/uploads/1/3/2/6/132681488/tedejusivive.pdfIn PDF document text
    • https://maminimavuzi.weebly.com/uploads/1/3/4/6/134640728/jisiser-jomokavodere.pdfIn PDF document text
    • https://zububeto.weebly.com/uploads/1/3/6/0/136082076/acfe20b1.pdfIn PDF document text
    • https://jerexibim.weebly.com/uploads/1/3/4/6/134654770/9981312.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475572/normal_603f68029cb7e.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://uploads.strikinglycdn.com/files/ffcf99fc-fdd3-4dee-aa17-ee8241735df6/warcraft_3_reign_of_chaos_vs_frozen_throne.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d2458682-2979-488e-841b-0669e3da6fbb/ditafogesu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b7128f1b-e1db-466b-9dbf-896da3348c71/gotilodinalanijawutu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/28f93112-58b2-476a-845b-d4dc3200e9ed/sword_art_online_progressive_volume_4_light_novel.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/77b017a1-03e2-4635-8df9-7ef5652d3fef/generalized_anxiety_disorder_questionnaire-iv__gadq-iv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/465b8f4f-a046-4c0c-95ed-e095dea0eae4/kunip.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a5ec2984-1eaa-4e6b-a742-a78082218120/5066130628.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA9E 5428 bytes
SHA-256: b3aa1e730c004591f3d7b5493a6d02b9fc2f8525b2c8257cfb22d6fd03a75034
font_01_sfnt_off0000fd2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD2D 10080 bytes
SHA-256: 568f59c9d54c0971ddb42e8878012f04d047276ce7c7a3ba1fb898c4937589f3
font_02_sfnt_off00011f9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F9E 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3