Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f81c208ec7cced0…

MALICIOUS

PDF

68.0 KB Created: 2021-04-19 18:31:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: f9efd624fb48d44e1b6a666d64e08d16 SHA-1: 5cbb8ac7de404a691e76f2b5a3e7ef289aa4596f SHA-256: 9f81c208ec7cced0d8a9dc4fed6e1a04c95e897590d7493b0015fc39d3914aed
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm, a common tactic for phishing or distributing malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or trojan delivery. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://www.osgeurope.com/sites/osg-corporate.dev/files/webform/fifomibap.pdf In PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/7486912807.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/togivem.pdfIn PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/29579557159.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/pexutagizoniged.pdfIn PDF document text
    • https://www.telluridescience.org/sites/default/files/tstc-applications/30232074114.pdfIn PDF document text
    • https://www.visitsavannah.com/sites/default/files/webform/fukixuliwidopisoduzurapi.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/todoxobolukajit.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/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=kenmore+ultra+wash+quiet+guard+3+resetPDF link annotation
    • https://minorsoncampus.princeton.edu/system/files/webform/wetesagepe.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/8342566550.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_off0000ccb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCB8 5588 bytes
SHA-256: a0753eebb2ecb3da0449d4deabd5db6265a4e38c43711a1d16188907db5f8641
font_01_sfnt_off0000df9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF9D 10440 bytes
SHA-256: 46ee7f204acc46efc1b5823038105cba9a0134ea91306e8e52425d8c413591e5