Malicious PDF — malware analysis report

Static analysis result for SHA-256 98c23e4639e2a2a3…

MALICIOUS

PDF

78.1 KB Created: 2021-06-20 07:52:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: bdbaadf0b7b3d783ca47ea40abb2e038 SHA-1: 4715583eb1204655f193670a5676395ad7d37c6b SHA-256: 98c23e4639e2a2a38d07faa34df7b7d529e7f73a73d1aee6e05a7bfc51aa222a
156 Risk Score

Malware Insights

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

This PDF file contains numerous embedded URLs, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or to serve further malicious content. The presence of link farms on disposable hosting and compromised CMS uploads suggests an attempt to obscure the ultimate destination and evade detection.

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://pixomot.ru/uplcv?utm_term=twilight+forest+dungeons+dragons+and+space+shuttles PDF link annotation
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160830ce2836a3---sidoxodozobexaxorafuri.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c160731b38b---zofonedorijunu.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9651251be---duwipitugurukukovu.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/8c4f2b99bd29a959ade1173e0aafdfd5/6217217608.pdfIn PDF document text
    • https://africanresearchcenter.com/userfiles/file/28798892896.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/penudugif.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/356fcade36a132cf4399882a648940da/91976957333.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/i04go6g3idl4i4h9bbbj8c2fol/7241044402.pdfIn PDF document text
    • http://alphasigmaoverseas.com/userfiles/file/20038576275.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bf4c06696a---bekozisakizexodusetavipu.pdfIn PDF document text
    • http://vasvaripalmuzeum.hu/upload/file/nunexopilorajiwafafekedun.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d636d4ba39---73216928023.pdfIn PDF document text
    • http://architettoseneca.com/userfiles/files/movaxikusaz.pdfIn PDF document text
    • http://mastera-mix.ru/ckfinder/userfiles/files/dabobijozadene.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/594a930f403ce3795b134f0e04594997/kukusinigab.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e593.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE593 5340 bytes
SHA-256: bbbea6cbbf9a579ed9976a9445dc3d3f776f9fe67c6c0eb6a3269e6991619bc6
font_01_sfnt_off0000f7c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C2 11040 bytes
SHA-256: 5846bb825eea17ef545437b599a94c7bac78068b85ff881b2b2d32d4fcf81884
font_02_sfnt_off00011d4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D4E 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361