Malicious PDF — malware analysis report

Static analysis result for SHA-256 86c37b13dc84547c…

MALICIOUS

PDF

66.4 KB Created: 2021-04-17 02:50:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: b6c3827ef2ea8e0cf4b328e90a138440 SHA-1: a7af6845c2cfe312b3644fb63a2fb5c0d6e0617f SHA-256: 86c37b13dc84547c415e53f8edee9695ae89cc3dc4fadd0040ffb83ff0781eaa
166 Risk Score

Malware Insights

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

The PDF document was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm and a social engineering lure. The 'SE_BROWSER_INSTALL_LURE' heuristic strongly suggests the document directs users to install malicious browser extensions or updates. While no scripts were directly extracted, the PDF structure and embedded URLs point towards a phishing or malware distribution attempt.

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://www.mainephilanthropy.org/sites/default/files/30695142459.pdf In PDF document text
    • https://www.jsif.org/sites/default/files/webform/54003515034.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/banofamuwidobekoke.pdfIn PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/4279473489.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/50635107556.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/61391242106.pdfIn PDF document text
    • https://aboss.by/sites/default/files/webform/vobefoxejajizagosoberob.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/zizepuniket.pdfIn PDF document text
    • https://www.termis.org/system/files/webform/nibobuzokojovafizuza.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/28693943460.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=multiplying+decimals+word+problems+year+7PDF link annotation
    • https://www.healthdata.org/sites/default/files/resumes/78922999772.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/37488496184.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/46273532178.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_off0000c6ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6CA 5812 bytes
SHA-256: c23573d55a76271440788f0f94e5a9b3a7b4f32ec7d684a67b3f3abe1337fa9c
font_01_sfnt_off0000daa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAA0 9936 bytes
SHA-256: b76721fa7597c2bff2228acdd8698c87c0aa4058bb57665b4fc7babeef625c02