Malicious PDF — malware analysis report

Static analysis result for SHA-256 2114a3a645a988ca…

MALICIOUS

PDF

116.4 KB Created: 2021-05-18 17:54:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 7f1d2b2edde8e021fb34c1e400ab3ad7 SHA-1: 80afa1a3983b7adfd3edb16ec165247ce99715c5 SHA-256: 2114a3a645a988cad5739cb664df9f5a8f772f375f551f1447450489e8e8dde7
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external URIs, many pointing to disposable hosting, suggests a link farm designed to redirect users. The document body, though heavily obfuscated, contains metadata related to 'wkhtmltopdf' and a biology assessment, likely a lure to encourage clicks on the embedded malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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 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://zajinet.ru/strik?utm_term=8.2+assessment+biology+answers PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4371005/normal_60261c5597c05.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499341/normal_605d33c1e33d4.pdfIn PDF document text
    • http://masozaxo.22web.org/tuwisetemumodepadulexo.pdfIn PDF document text
    • http://xemopubuga.iblogger.org/xemisinibixurepet.pdfIn PDF document text
    • http://fuxofexafot.iblogger.org/28115754055.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411483/normal_5fdd18933d7f0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4422372/normal_5feb9feb5fb83.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4427080/normal_5ffa51ac971b7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4493266/normal_5fd8d8a86304f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419629/normal_601aa8187e8f2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443325/normal_5fda4d6360477.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408172/normal_600c3585a4205.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469626/normal_60290c2eafedf.pdfIn PDF document text
    • http://wumagakex.iblogger.org/55628502055.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377128/normal_606220320b59b.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://mosupixozijet.epizy.com/fenisajexosogiwomedi.pdfIn PDF document text
    • http://tobesonev.rf.gd/vector_calculus_ebook_free.pdfIn PDF document text
    • http://nupabumafe.epizy.com/40664088373.pdfIn PDF document text
    • http://rusakarazixano.epizy.com/document_checklist_format.pdfIn PDF document text
    • http://kewupuz.rf.gd/20999416647.pdfIn PDF document text
    • http://pafemovokixap.rf.gd/sozideruwewewo.pdfIn PDF document text
    • http://luvibiw.epizy.com/7037327482.pdfIn PDF document text
    • http://jadupapobixe.epizy.com/the_healthiest_diet_on_the_planet_john_mcdougall.pdfIn PDF document text
    • http://zirejivotaw.epizy.com/because_he_lives_sheet_music_free.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_off00018b61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18B61 5600 bytes
SHA-256: bf10afe0ff18f1321c0e77d7176bdec8f3e58f8e453091d79fa2948692f3751e
font_01_sfnt_off00019e7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19E7B 11192 bytes
SHA-256: 783774cb6f6c8576251b73d42cce5ed801e8e582cf6b680cd5e8df32939d0464

Open this report in the interactive analyzer, or submit your own file for analysis.