Malicious PDF — malware analysis report

Static analysis result for SHA-256 011f91c85bf811fc…

MALICIOUS

PDF

88.4 KB Created: 2021-07-19 17:20:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4cf1b3a0865b0ba37ecde6cc0b51ce79 SHA-1: 6bc261ed24f915d0513e1b8ad4ff72d8fc449509 SHA-256: 011f91c85bf811fc375e9a91c4f308588813ef69a8a06f26d54f6a732b4dc8d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to compromised WordPress sites, identified by heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the link farm structure is a common tactic for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160759064ae6bc---vuneredapoxiv.pdf In PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ceaf6c953e---61510767203.pdfIn PDF document text
    • http://cerrutistudio.eu/userfiles/files/17262263928.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd63e8cadb---nafekenedojidof.pdfIn PDF document text
    • http://nprofit.hk/userfiles/xuwovujowusikaguwus.pdfIn PDF document text
    • https://motelandratecuci.ro/userfiles/file/zukerupiwug.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/tr8gv6fospl3i22563jgf5c0lp/suwipenuxuvedilutokotu.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/28958986284.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aca6a960752---50542785122.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f8e03ef918---64962731002.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/fusenodifen.pdfIn PDF document text
    • http://pc-driver.ru/userfiles/files/64914424493.pdfIn PDF document text
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/7efd2ca209638987e747bd8e684bb660/85185324884.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3c6a2de92d---vabuzepelusinu.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160711c90a2c25---vukemodakofesobikive.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/5f280fa7c8d2971db0a777fa1c55779a/84445925474.pdfIn PDF document text
    • https://akrmedia.no/ckfinder/userfiles/files/zerogowon.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bdeab034b2---tovijowamisediku.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/dolemisikenem.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6428fea46e---22756284037.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608ad5fb9a755---8345137670.pdfIn PDF document text
    • http://kistours.hu/userfiles/file/turavogonulili.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a479bab72c1---78600350280.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16093cf8b553ff---68174082436.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=the+journal+of+law+and+economicsPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f396.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF396 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010ba8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BA8 18236 bytes
SHA-256: b4c02f2c11163b8adcea4894207c3da343acced95a5ab723670f6128cdb9813c
font_02_sfnt_off00013b39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B39 10920 bytes
SHA-256: df59a55b3ca23bccab9623cd27ef3e55e7032f56b744abc2e822580ebcd16056

Open this report in the interactive analyzer, or submit your own file for analysis.