Malicious PDF — malware analysis report

Static analysis result for SHA-256 25a836cb3cfe3dd7…

MALICIOUS

PDF

76.9 KB Created: 2021-06-21 06:47:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 85ad3e0254c83fca960d43d579ba7188 SHA-1: 3de81b8c295d4d4921b58369673926bf231d36da SHA-256: 25a836cb3cfe3dd742b50428638f48ad655a81d6f9fa77f0b785083e16728065
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

This PDF document is flagged as malicious by ML classifiers and ClamAV, indicating it is a phishing or trojan delivery mechanism. The 'SE_BROWSER_INSTALL_LURE' heuristic suggests the document's content is designed to trick the user into installing a malicious browser extension or update. While no scripts were directly extracted, the PDF structure and embedded URLs point to a link farm hosted on compromised WordPress sites, likely serving as a distribution point for further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://dzbnf.com/upload/file/%5C/sazawilarujotamenumas.pdf In PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/1e6fqjv4fd8qqht212v9pfkkr1/68378897982.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160cfefc76c891---wapewipa.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1606fea778d544---kerapagafibubinonidepes.pdfIn PDF document text
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/508b2da1d9d48341a3075a03addff310/43038100331.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092194c492c0---folaxawof.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/siqg7husg93eckgvkd32ponc51/12926903986.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2196470ddc---13872738109.pdfIn PDF document text
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/kimuvofoxizan.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072766488387---81166494083.pdfIn PDF document text
    • http://vimar.ua/userfiles/files/35280916616.pdfIn PDF document text
    • https://www.federatedlighting.com/wp-content/plugins/super-forms/uploads/php/files/c4ed5034c9d48fbed3ecaec2dbcad900/36618987763.pdfIn PDF document text
    • https://nazragame.com/calisma2/files/uploads/gawatobubosarawolesalaj.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b783af6d2ca---faxalasawaraz.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/BkSY9tpko7c/uplcv?utm_term=guitar+rig+5+pro+presetsPDF link annotation
    • 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_off0000ea25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA25 5112 bytes
SHA-256: 1f76e781ce8568b8231d2f4c8f4752194efed9dfe60e51bc2fb7924db2e24ddf
font_01_sfnt_off0000fb9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB9C 13644 bytes
SHA-256: 4bf5249760564f66a6ce1026491009fdfcb8523cce16c8b6fa3f61a28e576f2a