Malicious PDF — malware analysis report

Static analysis result for SHA-256 5120f063d624179d…

MALICIOUS

PDF

78.4 KB Created: 2021-06-12 16:42:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 7a65deeb29e529bbd4d3b22aa5164ce2 SHA-1: 6e27ce511657e856563d1dbf5c53c8487560990b SHA-256: 5120f063d624179d7ecebe2d39eb23fe37c126a447cede8509f4161088d047b9
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create malicious PDFs.

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 https://infrive.ru/uplcv?utm_term=gotrek+and+felix+trollslayer+pdf PDF link annotation
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/c3c00baf0455d6ce8132f01096e8ffea/panupisezi.pdfIn PDF document text
    • http://thaoduocquyhiem.com/userfiles/image/file/34284649915.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/58476743200.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a76c164a7c8---61099352136.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/roj5ut76hq3g8krdv4u3jgk11r/30507575279.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/de9d0b3a25344c0a7fa279b3432d72b9/68808598728.pdfIn PDF document text
    • http://sanruou.com/app/webroot/uploads/files/xowulorelotu.pdfIn PDF document text
    • http://vaness-sens.fr/ckfinder/userfiles/files/gowuxabepubunarexozomaran.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2a0f5e9e90---91334241332.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607efee25332f---wadafajag.pdfIn PDF document text
    • http://gesundezellen.de/neu/userfiles/file/kedogugopudajefufewipan.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160ae484ebc405---69025150557.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16095b17dc8e59---75419043204.pdfIn PDF document text
    • https://houstoncoinshow.org/FCKeditor/file/45844871041.pdfIn PDF document text
    • http://taiwanglassgroup.cn/userfiles/file/5856867871.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/e1dcc6505355692894060a980d42b97f/23063748134.pdfIn PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/c11bfd2498abb138bf5eeff0ea4cb770/mobiwebiso.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_off0000f5e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E5 5300 bytes
SHA-256: b4a9e06e0f0d3d59856890738640ea97e869bd81baa06abd3b636ac7907ad8d0
font_01_sfnt_off00010816.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10816 10636 bytes
SHA-256: 698b44decc4db9ec03e8ce0c5cad1b77260adb8cb2d93f5737ec964964ede3b6