Malicious PDF — malware analysis report

Static analysis result for SHA-256 86a5e0cc91c31f3e…

MALICIOUS

PDF

70.6 KB Created: 2021-09-06 20:11:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 28bc50915f8658f5a9a17408ebb282fd SHA-1: 68c6da2312aac48655026f11260fd82fab8d6f46 SHA-256: 86a5e0cc91c31f3eaf7cf52afa73d0e9e24de49641b46752faf725d51ec59f64
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or are part of link farms on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://skiclubraonbaccarat.fr/pdf/91685672689.pdf In PDF document text
    • http://rustproofingottawa.com/userfiles/file/lilavilixixedunutuzumuris.pdfIn PDF document text
    • https://eccdc.org/application/webroot/userfiles/file/175321291.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/7668026527.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/80766527867.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d7be406afa---56571750625.pdfIn PDF document text
    • http://beateromer.com/bilder/file/12386983176.pdfIn PDF document text
    • https://mtmhomeschool.com/mycms/uploadedimages/editorUploadedImages/file/1702222622.pdfIn PDF document text
    • http://klubalfa.org/img/userfiles/file/wovovijubemapebami.pdfIn PDF document text
    • https://subded.org/userfiles/file/zagugan.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607daa7726940---datesetodizadu.pdfIn PDF document text
    • https://aurorabersinar2.com/contents//files/6932634066.pdfIn PDF document text
    • http://wenxuezj.com/images/File/63599938509.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/62vjtdd6fbkec6on7f1j55bn6g/38348004610.pdfIn PDF document text
    • https://irrisyst.eu/files/file/dimonoziripovosoxulovoj.pdfIn PDF document text
    • https://electroagro.es/pub/files/divefabakuwij.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160a2ac1d66f5b---11945985968.pdfIn PDF document text
    • http://absigorta.com/E/file/38142489406.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1609a03d474e76---8762629688.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f29bb39e1---33542139544.pdfIn PDF document text
    • https://tradingphrases.com/userfiles/files/52536935845.pdfIn PDF document text
    • https://zemiigori.com/uploads/file/45297176221.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611fef327fd41---zevokizasanozesagogaje.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1611b3fe602ceb---79294976722.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16117308c0e81d---28043716198.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608278cd7c70d---77188772430.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=download+pdf+reader+for+android+apkPDF 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://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_off0000b7e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7E5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cff7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFF7 15000 bytes
SHA-256: 40ff367dffaab0d3267e1488c6637ffb1b200065ba9e2c674084916413bff08f
font_02_sfnt_off0000f4b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B4 10404 bytes
SHA-256: a8dcac286df422c226cd81c0dd08db937034ea42e6d0369457cb796abd5cef32