Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d039994a2723489…

MALICIOUS

PDF

100.7 KB Created: 2021-06-27 22:22:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 0c34ed976f62d31b469842235da04c0d SHA-1: 39a362861ffee99457a1a4acf25846f52dcf4867 SHA-256: 8d039994a27234890488769a63ea539169e428d69700c85ec55732ec1296a662
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content or phishing pages. The presence of PDF-specific heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the PDF is part of a campaign to leverage compromised infrastructure for distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

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://crysiq.ru/uplcv?utm_term=bloons+super+monkey+unblocked PDF link annotation
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/716f981b21f65b96f261da2e15ed4d8f/mevisafajexi.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609158c46deb7---58764993841.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/40dfe581bea37da811dd09af8d4d3476/puxeleteselafavuv.pdfIn PDF document text
    • http://topas.lt/userfiles/file/sovajinodewebazarakopokus.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16085249255a9e---lapulejexaravudibefilom.pdfIn PDF document text
    • http://fincasotilloviejo.es/files/sotillo/_repo/file/78521119695.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/5b1468de25b64b9e9e4b6f32418625a3/bagazu.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/c16b7585de2acc9f8223998579042d8c/33474067629.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608240d4b140b---88099805327.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce0d565aaa---9513037437.pdfIn PDF document text
    • https://englewoodgrassfarm.com/wp-content/plugins/super-forms/uploads/php/files/8b87595715365e77dd250ed0c6f313f5/soramubiju.pdfIn PDF document text
    • https://go2germany.ru/files/file/25638434485.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/5f6485d04c2efed0a6adddb3ce892a42/fakodefo.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ab23db4189a---volukol.pdfIn PDF document text
    • https://bawaniint.com/ckfinder/userfiles/files/tuxafamoxesoto.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c04cbd7e679---63727130199.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/120baa0689166c527a046ab67ae7684c/dofunapikujo.pdfIn PDF document text
    • http://muzeumostrowiec.pl/obrazy/file/nuzawofetunum.pdfIn PDF document text
    • http://guoyangmoju.com/userfiles/files/36463024511.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/xovaxebip.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/khr00v82na9snl7ksiu32i5hvg/25127248227.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/n46bo7r4qavvj1b1jts4nnflvh/vovukomuxulirikawoboba.pdfIn PDF document text
    • http://braciszewska-klimek.pl/fck_files/file/47682382027.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/b620c4a27e5d56fab9156746cd30f3e0/64278258553.pdfIn PDF document text
    • https://www.latentoac.com/portal/wp-content/plugins/super-forms/uploads/php/files/s5fqr7nqskte44oqtf08f7l6fk/89475333213.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_off000122c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122C9 19008 bytes
SHA-256: 6021e621805a57b8506e16ead60def8017bdc152d41ce9c750ff1d00747b5f9f
font_01_sfnt_off000154ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x154AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016cc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16CC4 10820 bytes
SHA-256: 2e892e66a56cd9c2bad41f4c9ca7e70eb09f7c06c9cfc866586f18d0deaf2ad8