Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c9ff87d4b054717…

MALICIOUS

PDF

77.4 KB Created: 2021-06-21 16:49:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 67a275a4c51611d49c70132fe11eaccd SHA-1: 6f81c9dfd20cd6d9e964c7ceaaa83972b2dee691 SHA-256: 4c9ff87d4b05471772c7795bb8a984a4499817495f264205638fd187ffa5d02f
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress sites, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing campaigns. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver malicious payloads.

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://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/895378354897751b5677127cfeef8e9c/tenasorurar.pdf In PDF document text
    • http://wsp.pl/userfiles/file/junopinidatavak.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/12365326786.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/2dbcbf93f72e063ed3826d63960aea9c/80532937043.pdfIn PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/70fdacf63931eb76a3814423b5884c5c/20281781316.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/la8i6aujoaotuoto6a0ominl05/fidalu.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/54498951689.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e573a4c4b5---gikexuzitebivo.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160bb7499df668---10043832069.pdfIn PDF document text
    • http://healthywithhart.com/res/file/28529968279.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/cab3a17f5a97a8909c687915bbf58074/60277315205.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc9b98a1d6---tozebakipuzero.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/d29f4d9bfedda8ed6f219f71cf16ee29/gigafuwupepuvako.pdfIn PDF document text
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/311c8d795faa8dce8bb00a630da4b50c/tewiza.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160736464bb2b4---mimiv.pdfIn PDF document text
    • http://sam-global.info/files/file/24314667297.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/~3/1xuhb7AK25c/uplcv?utm_term=certificate+design+in+word+format+free+downloadPDF 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_off0000f014.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF014 5336 bytes
SHA-256: 4b40b0536e17e356d906e4d180b6335a5248a663a37450d04240618c1573836e
font_01_sfnt_off00010234.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10234 11088 bytes
SHA-256: 345409b62c59933bd9af05def1b58058c7e6d9f123f3623ef87c743676b18015