Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1ca28c13af4191e…

MALICIOUS

PDF

107.2 KB Created: 2021-06-23 10:27:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 4297bb09a2d46ed92229e21a34768c7a SHA-1: ca40a7c55db1d3153de967353929bf916ca2c6e2 SHA-256: c1ca28c13af4191efad9987de88c64750c3bee924838b294ee6e71370a1b133e
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm used for SEO poisoning or phishing lures. The embedded URLs and the heuristic firings strongly suggest this PDF is part of a phishing campaign or a downloader for further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://huntic.ru/uplcv?utm_term=prescott+microbiology+11th+edition+pdf+drive PDF link annotation
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/94ceb5e25a62f0e5a1f8b6bc199ef2a7/wirujukolop.pdfIn PDF document text
    • https://ancoraeducacion.com/images/xoporazepera.pdfIn PDF document text
    • https://artlabjo.com/userfiles/file/fapobogirujadivo.pdfIn PDF document text
    • https://andana.us/files/files/96906798140.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/2e8n40u7bt7qfg7qdurtlgbhlo/rakanevuse.pdfIn PDF document text
    • http://myjobcareer.net/userfiles/file/2021060304520573499.pdfIn PDF document text
    • http://billedbutikken.dk/articlefiles/file/2329380437.pdfIn PDF document text
    • http://birnagarcollege.in/userfiles/file/lemafolumalakakob.pdfIn PDF document text
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/c8fe89103b836895bb83b71a78323317/wunonura.pdfIn PDF document text
    • http://www.aadhar-interior.com/userfiles/file/97156660524.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b098a044b187a53d83a87aaa031ec360/xabirukaxalozukasub.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160bb02dfe2ac0---giwajani.pdfIn PDF document text
    • http://seabeachthailand.com/UserFiles/file/buvabutatemekubideno.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16095d38e790fd---lodenakasak.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/7616af62f85ed83c9c4f478db3dc214d/11861256745.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00014e63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E63 5716 bytes
SHA-256: 6b07104e1873dda717f0bce1bbf8065a40b5de9b9ecd76cf6225ea9d9dc2733f
font_01_sfnt_off000161b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x161B7 11728 bytes
SHA-256: e68b4fb8a05432392fd98bd206d0655d238ada8d4fe339b657e19c0bf5cda585
font_02_sfnt_off000189d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x189D1 16148 bytes
SHA-256: aabbb95e4258a1bccfe6759090a0a8b97a33e8154131110566ffb2eaa8fdb080