Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbc6c6088f0ace5a…

MALICIOUS

PDF

73.2 KB Created: 2021-04-13 06:42:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: f6c6bdba975599cecc49283622d645cc SHA-1: db79ca1bd8705391d095751ebcbfc4c90890352c SHA-256: fbc6c6088f0ace5a9466c7ff2bd4f14777c05716b1b89514d8dd23fb58ee962b
126 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution attempt. The PDF contains numerous embedded URLs, many of which point to potentially malicious or disposable domains, suggesting a link farm or redirection mechanism. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination. No scripts were extracted, but the PDF structure and URL patterns are indicative of a phishing lure.

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.natsihwa.org.au/sites/default/files/webform/bukitonixoravutewoluba.pdf In PDF document text
    • https://www.dgs-interparts.be/sites/default/files/jinez.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/42406093886.pdfIn PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/sizewavajifur.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/woximinel.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/21691652676.pdfIn PDF document text
    • https://www.visitsavannah.com/sites/default/files/webform/nodarinit.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/22435641867.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/25680057182.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/93477879009.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/32675510575.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/64296936159.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/wavunivuzabanovomid.pdfIn PDF document text
    • https://europa-ts.ru/sites/default/files/webform/81905598419.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/~3/3vuEKuznOb8/uplcv?utm_term=esther+gokhale+8+steps+to+a+pain+free+back+pdfPDF link annotation
    • https://lib.asu.edu/system/files/webform/sikukuditizituxabisezopel.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/popikinof.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/midari.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_off0000e13b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE13B 5772 bytes
SHA-256: 1f079149e5e812da7f418586d94a32433943b902cfc55624641895ce1153a369
font_01_sfnt_off0000f4d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D6 10592 bytes
SHA-256: ebc576b45dcace15ea37c1642bca3b17efe8a4d5c668221c67577ad8f2542aa4