Malicious PDF — malware analysis report

Static analysis result for SHA-256 2ca9235aeae8f875…

MALICIOUS

PDF

68.8 KB Created: 2021-04-08 21:35:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: ccc354244a631fc859bbdb62da74b88a SHA-1: 20f2e675161ca788b6b9b898c09bd7257f7a430a SHA-256: 2ca9235aeae8f875490a550ae45e55a47e656df6381cceda06b753ec0132581c
134 Risk Score

Malware Insights

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

The PDF document contains heuristics indicating it is a phishing lure, specifically mentioning 'invoice or payment language paired with an action verb'. While the document body is heavily obfuscated, the presence of embedded URLs and the ML classifier flagging it as malicious strongly suggest a phishing attempt. The ClamAV detection further confirms its malicious nature. The primary IOC is the suspicious URL found within the document.

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
  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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 http://klm3fg.grhosting.cz/sites/default/files/webform/files/todoxobolukajit.pdf In PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/bavowusakixonodokuja.pdfIn PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/fajabenofedutetigolexid.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/basolidigululaba.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/86947183128.pdfIn PDF document text
    • https://natsihwa.org.au/sites/default/files/webform/degajakuko.pdfIn PDF document text
    • https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/bariwogutal.pdfIn PDF document text
    • https://www.telluridescience.org/sites/default/files/tstc-applications/pagasumoxozodaxatukaliwus.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/60015669747.pdfIn PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/jalipoxelelikepobolid.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/10654010608.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/26511902049.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/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=bill+of+sale+pdf+illinoisPDF link annotation
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/wosevojowavinojefe.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/36479690150.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/58023923203.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/zotatati.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/jelozubunumi.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_off0000d302.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD302 4988 bytes
SHA-256: e1847b1f213ebd1973bef968f0f13c732c024a7ad77ef520413ec4cfa57c0d4f
font_01_sfnt_off0000e415.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE415 9968 bytes
SHA-256: 26534ced06518973b828c6c5d608b8035a99d04343f15e3c7e445fe2c50d631e