Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4f2b2d6b2bcf4cf…

MALICIOUS

PDF

68.1 KB Created: 2021-06-06 04:16:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 43450f258e130add2335482a8a1de28d SHA-1: d62fd86de7d9c55b1901492baa0eec4fe94b8802 SHA-256: b4f2b2d6b2bcf4cf6ed17e05a8bb5f8eaf5fa54b2ec09b03bbdcf8bc6716f097
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious activity.

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
  • 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 https://medvor.ru/uplcv?utm_term=free+printable+music+note+reading+worksheets PDF link annotation
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/16096aeb606e6d---25520978697.pdfIn PDF document text
    • https://lightspec.ca/wp-content/plugins/super-forms/uploads/php/files/b150d680295603402830b09a56cc4b86/lanojotomudum.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b0920e179af---70954994679.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5b3ed4c46---21305505014.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/b0d0186863794e0306b9f9591b2e66c0/waninarulifowafaran.pdfIn PDF document text
    • http://cuhs1981.com/clients/8/82/82ca37c076ec4232796cb58ed009bb3a/File/zewiduzifusijes.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/i1c24lt5e26ml5m3b3i4abf5kl/rapubizirakokuzalurid.pdfIn PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/2db808ed540f5d65e83f1cfe8ecfbdd0/69669288790.pdfIn PDF document text
    • https://www.stjohnhomelessshelter.org/wp-content/plugins/super-forms/uploads/php/files/b98a0a9fb311dd054cb2bc53dad9f8f4/86820080987.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160a718daa95c1---44654741906.pdfIn PDF document text
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/c2fd37d7d576e86a90b871173ddc167e/puvevizizokuzarixut.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/16070f70ee965a---nedudupufodalazet.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/qpgu7eb6scqn1i6eiohmlsjcd4/26806866817.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b9429f24071---xetazupelepugen.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000cdbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDBD 5736 bytes
SHA-256: 3a66e9ed50bfbaa231afed7c4739ae073d965b6fd7ef4d41cc3bcd35bdec1c0b
font_01_sfnt_off0000e11d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE11D 10000 bytes
SHA-256: 1da84000b29264861f71fa907491b878304ddf12dafea837b0e4ea5979580638