Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8875bf037f8acf6…

MALICIOUS

PDF

67.2 KB Created: 2021-04-25 15:08:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: b40eb62747d9cd8b0567298adc6bb710 SHA-1: 1c625d03e56566c766bd97971a1df9fc463cb204 SHA-256: a8875bf037f8acf6e0cd6399312397ddd56b09be96c1026f5e85357b3093c866
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 structured as webform submissions, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing or malware distribution attempt, likely leveraging spearphishing attachments as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://www.jsif.org/sites/default/files/webform/94808830073.pdf In PDF document text
    • https://www.viachristi.org/sites/default/files/webform/89070061484.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/69309865186.pdfIn PDF document text
    • https://www.jts.org.jo/sites/default/files/webform/96043924660.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/71502920023.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/jitebetususi.pdfIn PDF document text
    • https://www.woonsocketri.org/system/temporary/webform/makepepatamizozixijefawop.pdfIn PDF document text
    • http://www.birdlifebotswana.org.bw/sites/default/files/webform/sightings-sketches/13349970620.pdfIn PDF document text
    • https://www.afscme65.org/system/files/webform/11173368180.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/kobovigub.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/welukugipevodabarovefeweb.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/zomosazufexebale.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/51131620028.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/LPIa9PGmDLg/uplcv?utm_term=martin+luther+king+jr+autobiography+pdf+downloadPDF link annotation
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/77241298986.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/58023923203.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_off0000c9e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9E9 5604 bytes
SHA-256: 3dbaaeeea0769041fcfec4ccf8fce00e33645e99aeea822a1f25c71757b8c5b9
font_01_sfnt_off0000dd1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD1D 10168 bytes
SHA-256: 3c54feff617799d89e67c47bd5c73c6051516e47e0efaa1aaabc9d078386b890