Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6feeb7d8158b194…

MALICIOUS

PDF

79.2 KB Created: 2021-04-16 19:49:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 819c67d8d3e7db2939ba84d2fbe67d6d SHA-1: 41abff343bdde6ad0cced1aa2377ba240134f587 SHA-256: c6feeb7d8158b19436ef17081e3f82c1610ef585b5169aaad2bbc69dac8b6dbb
134 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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/wajuso.pdf In PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/65827293628.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/17947704001.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/sidetarebuw.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/topijetidilotifoga.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/wofofokarawivuboniju.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/futexapepunuvanujom.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/59680287402.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/21073527915.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/taxevoxasubosiwugudabi.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/FevRqgeaUVY/uplcv?utm_term=what+is+challenges+of+globalizationPDF link annotation
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/86402477901.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/4552140304.pdfIn PDF document text
    • https://thesanfordschool.asu.edu/sites/default/files/webform/83703622856.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/sikukuditizituxabisezopel.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/16616798570.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/94207829768.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/muvebijamalixodimobowase.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_off0000f62c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF62C 5248 bytes
SHA-256: a196e994e64788c10b5d3e5a44d7c5a060739137b1a7499a9a6c124567b2ccfa
font_01_sfnt_off00010828.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10828 11116 bytes
SHA-256: c2d2ea323053866d8dc4ba40c30e7ff0e93b69889ae65b35ec5ba934359ede5e