Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a9ac9947ff571f6…

MALICIOUS

PDF

79.6 KB Created: 2021-03-22 13:23:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 419f43292d708136c980ad41d2780dea SHA-1: e16567e89c0b15ddebb1fac52267c39562d203b5 SHA-256: 4a9ac9947ff571f6140e3ca06b481570c5ca078eefe406ba989ecf2a61e0b638
186 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, many pointing to disposable hosting services, indicating a link farm or phishing attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious activity, likely related to spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://vilenefex.ru/strik?utm_term=is+communications+an+easy+major+reddit PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4470232/normal_604b94ba2dec1.pdfIn PDF document text
    • https://jivupofa.weebly.com/uploads/1/3/1/4/131406879/weteme_mesoduzuwoja.pdfIn PDF document text
    • https://cdn.sqhk.co/satovepato/hmaigEk/vemoraro.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482228/normal_602d479b43118.pdfIn PDF document text
    • https://cdn.sqhk.co/xarozowuzosa/c8hehet/pijenalatapim.pdfIn PDF document text
    • https://gukofatupov.weebly.com/uploads/1/3/1/0/131070505/6326723.pdfIn PDF document text
    • https://cdn.sqhk.co/nuvuvidova/eIcjb2T/zadugusatixajonidakezuvab.pdfIn PDF document text
    • https://tabogivazosepa.weebly.com/uploads/1/3/1/8/131871767/1810150.pdfIn PDF document text
    • https://cdn.sqhk.co/ferudati/9sidjdw/ridogefeterunoj.pdfIn PDF document text
    • https://cdn.sqhk.co/likunubiba/hbyiiih/inspirational_stories_work_life_balance.pdfIn PDF document text
    • https://cdn.sqhk.co/pulurune/ZQhhVii/lefotevepegivatu.pdfIn PDF document text
    • https://cdn.sqhk.co/puburikob/hbhb3hf/jackfruit_cut_in_half.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446500/normal_60360bc166491.pdfIn PDF document text
    • https://cdn.sqhk.co/govizanorev/hoojihj/414025665.pdfIn PDF document text
    • https://cdn.sqhk.co/dobusalebed/eiejchd/petadadisajatojiwisoxalu.pdfIn PDF document text
    • https://vimitorumu.weebly.com/uploads/1/3/0/8/130814921/fdff72b371233.pdfIn PDF document text
    • https://cdn.sqhk.co/potiribuwuf/ieEVgjY/34017617860.pdfIn PDF document text
    • https://rokotejipap.weebly.com/uploads/1/3/0/8/130814190/pufinijoj.pdfIn PDF document text
    • https://cdn.sqhk.co/jopubelo/fjizFM4/52737595866.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://s3.amazonaws.com/dugibabafod/kingdom_rush_frontiers_achievements_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/lupebesu/fuvusodixevev.pdfIn PDF document text
    • https://s3.amazonaws.com/wazorixekunafob/volofoke.pdfIn PDF document text
    • https://s3.amazonaws.com/pululusodogi/45576060756.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_off0000ebf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF8 5048 bytes
SHA-256: b855b7000ef3558b66e62b7bf71dbda86739214487ad020e688d328fda55af04
font_01_sfnt_off0000fd06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD06 11092 bytes
SHA-256: db56b723319daaef6347d3997bdf25051ac2f1f9aa8c424ed47b6778a33cc2b6
font_02_sfnt_off000122e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122E5 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3