Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f52ace83a67982b…

MALICIOUS

PDF

71.5 KB Created: 2021-06-10 02:55:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 69cb14def1d5343adff3acbe8f6323f0 SHA-1: ccc65c356020d912670aec98ee5180eb6e15d604 SHA-256: 4f52ace83a67982bceaa964456ae92069a816dfe1ca9b294c47e65bdb9222198
164 Risk Score

Malware Insights

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

The PDF document contains numerous links to external websites, many of which are hosted on compromised WordPress installations, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The document body, though heavily obfuscated, contains text related to document conversion, reinforcing the phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://inwebjor.ru/uplcv?utm_term=convert+document+to+word+online PDF link annotation
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/c0b53e6bf0c9c7b6c5a566670cce9050/86898121596.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080d32f88a7b---26241487342.pdfIn PDF document text
    • http://cosmickino.ru/sadm_files/41222144433.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609258a0c7b3e---pupuwosotixu.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/c9b91bdbf9ce1ed3d8b9426e097a87a7/61073265469.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/587a197f5d8381367190a502c941928e/97809773947.pdfIn PDF document text
    • https://armagedonspedycja.pl/files/file/gazanogetovijurudonijano.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085fd3abc027---78853837942.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/p09oi8r1318sucgd48pdtp5ac7/fofekavugonup.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/5a3ebdd7428c87d56f2476eeec0b0c42/tudovufomalotidapovepek.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/zuxomodagotukarut.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1606efc33291a7---wodosuriremizibopunosonur.pdfIn PDF document text
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/1dbdd8cc30bc58f3e6783f6fbff23efc/fatutu.pdfIn PDF document text
    • http://filtrydokoparek.pl/img/all/3867358705.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_off0000ddf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDF3 4756 bytes
SHA-256: c77ba9fd5e3850a699d62027aedc909a62400b8c8cad18c545d83d6bbc582b29
font_01_sfnt_off0000ee18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE18 10280 bytes
SHA-256: 4a0a7af1d73293a0001301b6dc54d7afbaa54d655c5468a90c35c83a591187b0