Malicious PDF — malware analysis report

Static analysis result for SHA-256 67bbc2871120c37f…

MALICIOUS

PDF

70.8 KB Created: 2021-06-12 20:18:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 670af8f0696cf639c2d62d27c93a34cb SHA-1: 000dce5f3a535db1e232fdc17d5e6f8b9b0991b7 SHA-256: 67bbc2871120c37fb4e7646898f294901a80b9ef13498b47e40e8394633d8a17
156 Risk Score

Malware Insights

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

This PDF document is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It employs SEO poisoning tactics by using keywords like 'grammar worksheets for grade 5 with answers pdf' to attract victims. The document contains numerous links to external sites, many hosted on compromised WordPress installations, suggesting it acts as a downloader or redirector for further malicious payloads.

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://synerhu.ru/uplcv?utm_term=grammar+worksheets+for+grade+5+with+answers+pdf PDF link annotation
    • http://maydangson.com/vietkiendo/upload/file/21611720428.pdfIn PDF document text
    • http://buildinggodskingdom.com/webcms/file/94125255405.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bfbfa36a3ee---tefolunovukowa.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/2gkj8lnvjnhsd0ef6t22jueini/35673890581.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2390d13ab7---guxobabofe.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/befcf943d81c5f2ef7bfb9029c3f2458/17568238310.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/49637886052.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/r2gek894b7sfnaqjcohca6013l/xelav.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/9dotjlmt0k5imj260dpqhghh02/jibav.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160bf3305114b4---zulujivadajaxur.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bc124853409---3987166919.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/cjm816g9f7lp3rqgef84t89ep5/lofejubukaguvef.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a96b61c003c---43837890799.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a250d9556aa---fowumusoroze.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/mpmv79g21v6br01db537hqr4t4/tepijafu.pdfIn PDF document text
    • https://cape-electronics.com/media/file/marubepegomig.pdfIn PDF document text
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/vt30qgjiblfltua3f9ent7caft/zelupotelibej.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_off0000d665.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD665 5736 bytes
SHA-256: 15ce5458082dca29e6f20d11cbeb31a84a8e769844dcaca10b3535bea7b12c6c
font_01_sfnt_off0000e9e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9E2 10684 bytes
SHA-256: 0f65f0bfb2ea95f6d608cde329e68d327901fd83fa5ed9330dbf55f8118ad5c3