Malicious PDF — malware analysis report

Static analysis result for SHA-256 1dc547bbf3411dbe…

MALICIOUS

PDF

98.3 KB Created: 2021-07-05 13:47:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 9b6e409a946b133f3381edf949240652 SHA-1: 1aa6d49a926571c18194af70133eb24da1687672 SHA-256: 1dc547bbf3411dbe643aa2ae0ecc90aa5bdd582ff1633d89c2bacedfa685f6f3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress sites, suggesting it functions as a link farm for SEO manipulation or to distribute further malware. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/f136f33f943a7387243a9f8116847bb0/7171072535.pdf In PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/s7e1h0o7ogommh4qicblp331b3/tuzedujis.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160763391f3d96---zuzop.pdfIn PDF document text
    • https://dcmheavyequipment.com/admin/images/file/66909361333.pdfIn PDF document text
    • http://harissarantis.com/userfiles/files/sewoj.pdfIn PDF document text
    • http://anatolianlgs.com/userfiles/file/mimupozagajif.pdfIn PDF document text
    • http://abpaluso.com/upload/file/49882746498.pdfIn PDF document text
    • https://sarujiovalente.com/wp-content/plugins/super-forms/uploads/php/files/evk4pgpt2ih91lk9gruge1bb3r/pimexidovij.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608665298adcf---41267163404.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/02d5701e40a715b98f3d79d76f5b93ac/60845158397.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608121ffd14e0---9906708547.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609e80c0b5a16---58534990286.pdfIn PDF document text
    • http://hbleg.com/admin/userfiles/files/26292666940.pdfIn PDF document text
    • http://championshipsportsrings.com/clients/23492/File/rokilomol.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607e82cf7fdec---7160124225.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/1ec2b497379d7f2a198ad55e66224cf2/gadugilukifexebilakeka.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b61a1a9b857---lobenemesozumi.pdfIn PDF document text
    • http://vitalchurchesinstitute.com/files/file/tumovezowutekivi.pdfIn PDF document text
    • http://ledson.ru/upload_picture/sugifuserizovumage.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e6b0ec0ce2---77771973652.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/20b6cf6f4b674b4d87988c2285c800aa/nobapepofoxozuvuri.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160977853f369a---9426082400.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/d71d31f2e71ffe9761dc98f5e2fe83d0/97465426348.pdfIn PDF document text
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/c6d9847027d10cf5af88b95d04521287/jikarorawufuret.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=commercial+banana+productionPDF 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_off00011da2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DA2 17476 bytes
SHA-256: b6e3b0d14709bcdd49212c3789f3395f21bb35391353ef4d79f7fda51cac5883
font_01_sfnt_off00014b8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14B8F 10776 bytes
SHA-256: f42b6e1c401e63f1590d13951860d11c0a11f0b5c0ad47bd4212c77bcb18fe3c
font_02_sfnt_off00016413.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16413 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1