Malicious PDF — malware analysis report

Static analysis result for SHA-256 21a5a59bcbc3966a…

MALICIOUS

PDF

89.0 KB Created: 2021-06-15 11:58:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 83b4e140ac9a08b9512bc4b7f1495d3e SHA-1: 639c4495d2f3f38d452610e8a2e82a4812b1da57 SHA-256: 21a5a59bcbc3966a5630d8975c31cf186afe8518d380c878ad43f5b6b538f14a
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting it's part of a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

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://queure.ru/uplcv?utm_term=guilty+gear+xrd+revelator+dizzy PDF link annotation
    • https://a2designbg.com/userfiles/file/57151295099.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/qdjbdvreubc5vijma975grf0tp/jateziguxorewigekotipaj.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160ba839ee40b7---67434003657.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/kantcjsa326ecs5ufneb28ke4q/42169675223.pdfIn PDF document text
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/e88785f510c86a339be1f705f7a6f300/zidawur.pdfIn PDF document text
    • https://immo-cjeanpaul.lu/userfiles/files/29001493271.pdfIn PDF document text
    • https://zionapostolicministries.org/uploads/file/kexozovegugarojo.pdfIn PDF document text
    • http://paillasse.hu/userfiles/file/xonimub.pdfIn PDF document text
    • https://cottingham-group.com/cufiles/files/baliliwibufuv.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/16083258eaa4a6---wusiwadika.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608387e7dd681---82347087812.pdfIn PDF document text
    • https://theatresaucinema.fr/uploads/file/tipomudirujakezujepes.pdfIn PDF document text
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae4918d03bc---74159326950.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608ec96a76562---4914774300.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bc14d61dd60---nokuwapipin.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001044d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1044D 7132 bytes
SHA-256: 9aba9f935b4649b04fbf043fac7fc8252a50a344684c3aefd540b056c664b555
font_01_sfnt_off00011c82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C82 5124 bytes
SHA-256: c1d5993687bf3e0f2e1f45a9e42d6a20f4a794fd9d313c9a337055d035a5c656
font_02_sfnt_off00012e1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E1D 11864 bytes
SHA-256: 09df3fe664a7e8a5d88b033aaefd4a0196ce45623590f34542305eb9f5461601