Malicious PDF — malware analysis report

Static analysis result for SHA-256 84a40cdcfbd983ff…

MALICIOUS

PDF

61.0 KB Created: 2021-06-23 12:58:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 3f0097fa3995b60504e5b7a14f26a996 SHA-1: 5e57a42f282a75ee3325bb46e24dfc7028beca56 SHA-256: 84a40cdcfbd983ffbbb8302f668d5ec0fb33c2d6fe70e12224fe11507ee8d58b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to compromised websites, likely intended to trick users into downloading further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as a phishing trojan. The document body, though heavily obfuscated, contains metadata related to PDF merging and the wkhtmltopdf application, suggesting it may be a lure document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16076737bdbe7c---81839352092.pdf In PDF document text
    • http://montaze.org/democms/userfiles/file/61039154506.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609d45a0dd154---fugupisiboravukawi.pdfIn PDF document text
    • http://agriturismofattorialucciano.it/ckfinder/userfiles/files/tevode.pdfIn PDF document text
    • http://perseverance.cyou/updatefiles/file/94631391150.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/da75b7814396a9acf03bb6d8f449e1fb/23713762334.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160705c49e4401---18811241310.pdfIn PDF document text
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/9b690ed5926243bb7864fc5015b1b89c/60232836958.pdfIn PDF document text
    • https://watertorens.nl/userfiles/file/58946613514.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd7094658e---misaguwonebapesozi.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9836eeba94d8ee8fd2f056f0444fdb75/14051458476.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/4f1d7393d7a67e49e20a1725d6cdb06c/xemojazib.pdfIn PDF document text
    • http://paykaaluminiya.ru/ckfinder/userfiles/files/tesabijox.pdfIn PDF document text
    • http://salondebellezaanamariaromero.es//ckfinder/userfiles/files/wufutajenumigemujuf.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/51618773008.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/YTWXjIUwRh0/uplcv?utm_term=merge+all+pdf+in+one+pdfPDF 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_off0000b49b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB49B 5036 bytes
SHA-256: 2b6c12e87bb839e8794f50af2a61b9b549122acb183c4297dff97dea27c804ff
font_01_sfnt_off0000c5d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5D9 9896 bytes
SHA-256: 5e33497abd599dcac863408542be236b945147289c159ecc8e336240114a324d