Malicious PDF — malware analysis report

Static analysis result for SHA-256 598b213173bd57ec…

MALICIOUS

PDF

81.0 KB Created: 2021-09-07 03:16:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9aae18d65972ffc76c07e952f724a407 SHA-1: bf6dba3a48b61fc4b809f470a491833b85b5887c SHA-256: 598b213173bd57ecf16e115fb1d995b0dc8231b3ae85db3af3b66b235592c0ec
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely involving exploitation of PDF vulnerabilities to redirect the user. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://crysiq.ru/uplcv?utm_term=difference+between+academic+writing+and+non+academic+writing+pdf PDF link annotation
    • http://a2hgghk.handylover.com/upload/files/seduronu.pdfIn PDF document text
    • https://steammining.com/userfiles/file/ledetubulifilakalunira.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b06ec51cf5---7168121072.pdfIn PDF document text
    • http://podushka.by/files/files/13278355519.pdfIn PDF document text
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/d3497dcbdbb0822911116b79312c4d6e/jaxupuramuwoketaril.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/582e9133f329740878bff7dc72855d2e/44790382968.pdfIn PDF document text
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/3e16c97913d4c7ea6319c52dafae57c6/mukivepipepozolevotos.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/q9kilbik1ea0tuseu1u958nhb7/butukubajigakarozoxiropi.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc2ae80aca2---votoremivowi.pdfIn PDF document text
    • http://momsystem.ru/public/file/95219294555.pdfIn PDF document text
    • http://praguetransfer.com/files/file/38349945413.pdfIn PDF document text
    • http://gptools.net/userfiles/file/39634902724.pdfIn PDF document text
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/c30e678d82c6b4f2b7152870d4892c74/fonugopeti.pdfIn PDF document text
    • https://prawobrzeze.info/userfiles/file/taziwe.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/42715831822.pdfIn PDF document text
    • https://tunhuaduytan.com/upload/userfiles/files/morimuw.pdfIn PDF document text
    • http://naturalfurnish.com/userfiles/file/71155968677.pdfIn 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://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_off0000d586.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD586 10976 bytes
SHA-256: 083d79ca81f9807273ca6d1d9a94c3491ee8650a230659615ff1ba3d895d4098
font_01_sfnt_off0000eea8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA8 18120 bytes
SHA-256: 0ded16739a8693c7f44f4630a016ad548ff4fef5fff708560440f0781ee03499
font_02_sfnt_off00011dbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DBB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1