Malicious PDF — malware analysis report

Static analysis result for SHA-256 7836b4481a450ebc…

MALICIOUS

PDF

77.7 KB Created: 2021-02-25 12:04:03 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 5e168eaa1e4fe0237a003793f89ccf74 SHA-1: dc987a20b978dbd36436909bc1f2d5ed068ca278 SHA-256: 7836b4481a450ebc1b5e5602e977614ef25bfbfce70ac95e36cb46fd325e7134
126 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous embedded URLs, with the primary one being `https://druttle.ru/strik?utm_term=what+are+prevailing+wages+in+ny`, disguised as a search result. The heuristic `PDF_SEO_DISPOSABLE_LINK_FARM` further suggests a malicious intent to redirect users through multiple disposable domains. No scripts were extracted, but the presence of external URIs and the overall detection profile strongly suggest a phishing attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 5

  • 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 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://druttle.ru/strik?utm_term=what+are+prevailing+wages+in+ny
    • https://gikatufezido.weebly.com/uploads/1/3/4/3/134338368/fuluvepubopaw.pdf
    • http://lobabinuladeri.medianewsonline.com/charter_remote_setup_new_tv.pdf
    • https://cdn.sqhk.co/bezakebijuk/jahcRgj/fisokuwujaz.pdf
    • https://cdn.sqhk.co/vonixilavot/jRhdUgc/figip.pdf
    • https://vepibasizux.weebly.com/uploads/1/3/1/3/131380915/loditikifijekib.pdf
    • https://lenexemumuvag.weebly.com/uploads/1/3/1/4/131438583/putuwe.pdf
    • http://selozufuwadapuw.66ghz.com/25860522156.pdf
    • https://cdn.sqhk.co/zisenusaf/b6fAjVd/vukajanusekekusa.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://rojomiv.rf.gd/42618106563.pdf
    • http://kaderuzaxaje.rf.gd/fabimoremewevixik.pdf
    • http://zuvigedegoja.rf.gd/julitutit.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f2c7.bin
8ccd8dc7a87ccb895a7ff70eef3be968e2fe3252784c954a5dbd70234b488552
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C7 5348 bytes
font_01_sfnt_off00010515.bin
9835c2412afa5276a77035c916f5f379935a4fe6ad21d21602b422bca952a27f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10515 10924 bytes