Malicious PDF — malware analysis report

Static analysis result for SHA-256 eaff441dd1e02a81…

MALICIOUS

PDF

109.9 KB Created: 2021-06-17 21:52:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: d4d81a271c0a96bfdbad919cf84c09f8 SHA-1: 7885516101301eaa42a6c0f7420f4bfcd16553f8 SHA-256: eaff441dd1e02a81d6c64afed652db18181d1592946bf49952c679a5bc0de729
156 Risk Score

Malware Insights

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

The sample is a PDF document flagged by ML classifiers and ClamAV as malicious. It contains a link farm pointing to compromised WordPress upload directories, suggesting it's designed to host and distribute further malicious content. The presence of external URIs and the nature of the heuristics indicate a likely phishing or malware distribution attempt, potentially delivered via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086913dee115---nukavogusawam.pdf In PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090ac9a33121---kapowotaninikunemojubilew.pdfIn PDF document text
    • http://keralabiblesociety.com/fck_uploads/file/72872027713.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/16092f5e69db75---vuwilofokosez.pdfIn PDF document text
    • https://havanic.com/cache/fck_files/file/vabanatepuxut.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/01eb52c62ce7f6f9f528210057fc86e6/dinigajukovojef.pdfIn PDF document text
    • https://www.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/ahhuc2p8r5q86edjqkco96q0mr/debixinogadelasidenegop.pdfIn PDF document text
    • https://lamthong-marchph.com/piceditor/file/39200806871.pdfIn PDF document text
    • https://ketdoanbus.com/webroot/img/files/85068744038.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160bdb281e4879---wolarabagij.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/68174031314.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f9c039d233---zamitevezekidesakimis.pdfIn PDF document text
    • https://www.varishastalari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160850bb29a9aa---99994056381.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160927aae35904---rumusa.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606d948da9e20---31361831857.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/fzgW7-mxBc0/uplcv?utm_term=fake+online+wedding+certificatePDF 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_off00017128.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17128 5120 bytes
SHA-256: f17cf8e1ec83bca6fa9b50564224eefb1164b921353775404b5ba51bfedc2bb2
font_01_sfnt_off000182c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x182C5 11080 bytes
SHA-256: f7db5659ae0f062afe12e3db0272045be9d1d1ff43e998a202aceb7f31db77cd