Malicious PDF — malware analysis report

Static analysis result for SHA-256 37acbed7cc57200c…

MALICIOUS

PDF

79.9 KB Created: 2021-06-10 11:45:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: fd2036f6034eb7f5f4c1da5c7a67340e SHA-1: be1d65b6850a64951a921863d22e8bbadc62783d SHA-256: 37acbed7cc57200cd2ff9da788d208a02bfe4459e3caa17ad56e97ba6556e014
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal a link farm pointing to compromised WordPress sites, suggesting a phishing or malware distribution scheme. The embedded URLs and the nature of the heuristics strongly suggest the document is designed to trick users into downloading applications, likely as a lure for further compromise.

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://cructi.ru/uplcv?utm_term=all+web+series+app+mod+apk PDF link annotation
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/4a9adc2aca370893c2eff2a1b494e01b/43774331605.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/62243881586.pdfIn PDF document text
    • https://tipresentoio.it/images/file/26837185438.pdfIn PDF document text
    • https://art-lamps-rali.eu/files/file/42296682278.pdfIn PDF document text
    • http://ozdoby-betonowe21.pl/Upload/file/34736148528.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f71ec053ad---ditomopebalewexuvaturon.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/34e29508ce7eb58993b74cb5d5b25ce1/19884847191.pdfIn PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/4937f6ef3adf5d491b47eb1a8602e866/72020224342.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/15772050c5364061beedb7bd6b30ae1f/wezexuwuxider.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/5fd190f48b8666b4ed4a8b64916990ee/94225232254.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/verirejijaxejaxa.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607f25c76f901---79692762472.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf0c5da6be5---99170425939.pdfIn PDF document text
    • http://tilestone-pools.com/i/File/kuwariben.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160805b7bbd9b1---jinam.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160765781ac465---24034772679.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_off0000fa30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA30 5392 bytes
SHA-256: 1d7d7c9d3bc88b308166a8eda46b74c733ae801a778aa895006fa5a9ac8ac31f
font_01_sfnt_off00010c76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C76 11316 bytes
SHA-256: 3cf6a24d68e79e258eb6f89fba86b868fb996e414be1b75f0e11a1123081653e