Malicious PDF — malware analysis report

Static analysis result for SHA-256 821cd7a009066a4e…

MALICIOUS

PDF

97.3 KB Created: 2021-07-01 20:35:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 687769cb4bf177dc0a0b1e67215a0277 SHA-1: c303bda195a45604f16bee369a29f5cef777470c SHA-256: 821cd7a009066a4e5b5829d264ab5a5020ee0cf60662bd2341a66cf4cd1c8c82
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable hosting, likely serving as a distribution point for phishing or malware. The presence of external URIs and link farm heuristics strongly suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9930

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://wastran.ru/uplcv?utm_term=day+in+the+life+of+a+mortgage+loan+officer PDF link annotation
    • http://debden.org/userfiles/file/3450729526.pdfIn PDF document text
    • http://pospatrans.cz/UserFiles/File/vivaperumufatebuzezat.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c296f608a9---14844726790.pdfIn PDF document text
    • http://thessalonikiflights.com/files/files/55631486424.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160962f4df005a---lakabafuvodonivejuk.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/7a40c776810d0d4e314e629d620ad4a0/rivojizopotezepuxel.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/1c888fcc1cad1bd85240519fdc279fe8/7358957645.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160862013b6143---bojopepemijed.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/9a4216e4fb46af79ab5e34f0307ae10f/76986190755.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071a61e614cf---26804390693.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/wizeg.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/3842bc1bcb43baac9cb42c443d0c8cf2/sixokagulabixe.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/af39ffe0220c85917a8ee1fe5666820e/xinid.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/283b5daeef93c7de8010ca201ded7531/wikoweroxazozuritoz.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b7ff79f0840---18529999593.pdfIn PDF document text
    • http://rc-modeller.se/images/file///bosidoso.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c26388b64a---9524795641.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b31b17bb8da---50874286692.pdfIn PDF document text
    • http://berbun.com/user_img/file/jibobuken.pdfIn PDF document text
    • http://pnmanagementsolutions.in/uploads/28317779029.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a44b23b730c---4011161176.pdfIn PDF document text
    • http://innotec-industrie.be/userfiles/file/wilazavodugebos.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/db8c7242387930dcb69dd784f3f8dfd7/monebugesaleg.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160ddd77353784---65388858937.pdfIn PDF document text
    • http://drwatsonsr.com/clients/2/2b/2b9a0cf27321ceab3a47fbd10bf94d34/File/kevamos.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_off00011a83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A83 17180 bytes
SHA-256: 63e0ea124202f7fac2e9d51e558d6602c817a945202a1942e06e6c1d50d4456c
font_01_sfnt_off00014722.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14722 10728 bytes
SHA-256: 7ab3b6b72ed708a9f1b6853070d2455423b3efaed8c7c8510435528cf8bda114
font_02_sfnt_off00015f97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15F97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1