Malicious PDF — malware analysis report

Static analysis result for SHA-256 87dca6bead4c3819…

MALICIOUS

PDF

71.4 KB Created: 2021-05-26 01:26:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: ab868ddda579bcd5860f3f9d27fa3cd4 SHA-1: ed1adff9d78a16f29550480ed21fe405e9d38768 SHA-256: 87dca6bead4c3819b97fa59aaef7ef2cdcae29df702eb798bfd64e47ddfd48e4
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous URLs pointing to compromised websites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The PDF structure and embedded URIs are indicative of a phishing or malware distribution campaign, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://nomylo.ru/uplcv?utm_term=hipertrofia+de+columna+de+bertin+ultrasonido PDF link annotation
    • https://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/bd2b7ed4c557f4ba22146cfa38083f5a/najiterivezobikagufumugid.pdfIn PDF document text
    • https://bbpartner.cz/userfiles/file/45199841985.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160724fb29467a---fixapuwojugir.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16075658f6259e---9199326108.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16071a6ee87058---53302677014.pdfIn PDF document text
    • https://audit-advisers.com/userfiles/file/82601213878.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/e09b0485ad1951810a75f7bdfbf30998/78800156317.pdfIn PDF document text
    • https://hondamienbac.vn/userfiles/file/bipaz.pdfIn PDF document text
    • https://acronimocostanzo.com/userfiles/file/10699916400.pdfIn PDF document text
    • http://cy2hand.com/userfiles/fowesidimasefaluko.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608b669bb026e---gewetiwol.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/4aa8feeb4499e5f2d6a655a02610aa02/gaxuvevota.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/a1d49ff826ae453b1dc075d02fe61134/rowetiluvusubixuj.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/e3df69ea30b8cd156feefa503ae2c698/36495148932.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/02ecb23f7c7dfebec73195d7c523150a/jikuvat.pdfIn PDF document text
    • https://www.bistro-e.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc2a78d9ee---zojuvixunetoj.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C7 5404 bytes
SHA-256: cc8dc51c6f7002b15acf104c751066d3f1028932aac5aad371f76769beae195f
font_01_sfnt_off0000eb06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB06 11584 bytes
SHA-256: 4f7ee36247b7c80c56b0cc93f8b34fba0d75aff787afe52fe099d4d010fbebf8