Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb535644ecaf4877…

MALICIOUS

PDF

78.5 KB Created: 2021-06-11 20:13:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 9ecd7120b4e570a00d8e9fd31897c0af SHA-1: 2a838f85c106cbfccdf07625a1c8aff09f68e8ed SHA-256: fb535644ecaf48773ba935c604c94a1b0121c003a05ea538e3a1ea1d5f18f27e
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://infrive.ru/uplcv?utm_term=secretary+telugu+novel+pdf+free+download PDF link annotation
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/16083857783ac1---nabumigopinikegapuzib.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/sopobiges.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608c344a00325---17170979994.pdfIn PDF document text
    • https://hiddencliff.kr/FileData/ckfinder/files/20210611_B01AE6AE4E471B99.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160869b583ec0c---zopelokojajavukunafofilar.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a39b0004be4---nupenezedumokavajapiru.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160aba7cba5f94---fajig.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160bd3fc76288e---82674552328.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/0742ce9aa8bf51bd2f649d75fcd16fd6/38336579653.pdfIn PDF document text
    • http://www.assignproject.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a15bf0a45a7---rixiletat.pdfIn PDF document text
    • http://accomplishtheimpossible.com/userfiles_ati/file/tadanediradadagojutagut.pdfIn PDF document text
    • http://paradisoseminatrici.it/userfiles/files/99525135821.pdfIn PDF document text
    • http://atek-ent.com/upload/file/86710766011.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d9ed37b94---67851785636.pdfIn PDF document text
    • http://happyhanool.com/ckupload/files/72098205362.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/o0qodiolj0ocbjhd09hbtamv21/55237232872.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16094bcacb7718---82365967082.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607483febb895---62652717182.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16078ecb50fd84---33985553804.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_off0000f544.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF544 5500 bytes
SHA-256: 9ba868a2bba8531dbc008bbdd3ce8713198592abe6948747af2c4fcaa1096c3f
font_01_sfnt_off0001082b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1082B 10812 bytes
SHA-256: 3826f2c7e28f8e767273ff26fc26a450056b87d5084119904ea5c20b1dfd85ef