Malicious PDF — malware analysis report

Static analysis result for SHA-256 160dba9d1a5014f6…

MALICIOUS

PDF

67.6 KB Created: 2021-04-23 01:43:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 4e262e0cae74896e7046b21490bd2524 SHA-1: 0d2f3b0a829d70b82486f91592fdd2e454d03510 SHA-256: 160dba9d1a5014f634b0b559167b9f768eeb04ba87620c4ede17b82e55456df4
126 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic analysis identified it as a link farm with numerous external URIs, many pointing to potentially disposable domains, suggesting a phishing or credential harvesting operation. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a spearphishing attachment designed 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.telluridescience.org/sites/default/files/tstc-applications/fezijorimofilafomifum.pdf In PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/48862039041.pdfIn PDF document text
    • https://aboss.by/sites/default/files/webform/vobefoxejajizagosoberob.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/59286961246.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/joxelivoresilawefuxeli.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/gegemapoxazokex.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/wozupidojenebimovom.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/xojisipet.pdfIn PDF document text
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/falaburisidibiwad.pdfIn PDF document text
    • https://www.mainephilanthropy.org/sites/default/files/5296457674.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/dekif.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/69309865186.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/A3Ryygt5BCM/uplcv?utm_term=sodastream+co2+canister+refillPDF link annotation
    • https://www.vub.be/sites/vub/files/webform/86005813007.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_off0000c847.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC847 5400 bytes
SHA-256: b62fcb46966c23f59359107da88b1c7962850f9ac048f83a2182c06edf1d81f1
font_01_sfnt_off0000da92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA92 10924 bytes
SHA-256: d89d2bf161b865d295a6fc5fabf0d8329292570a5b3c8068bed3b2573112c23f