Malicious PDF — malware analysis report

Static analysis result for SHA-256 99fe448403e5b187…

MALICIOUS

PDF

72.0 KB Created: 2021-09-15 16:25:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9e4fc611e4562ed08528bff550f4a330 SHA-1: 36ab78fdff67d38a9be1ead873033c6fee6fefbe SHA-256: 99fe448403e5b18774f9acb2b8d35a70ea481e8e6f164afd51ef2675b9130a85
156 Risk Score

Malware Insights

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

The sample was identified as malicious by a ML classifier and ClamAV, detecting it as a phishing trojan. Heuristics indicate the PDF contains a link farm pointing to compromised WordPress uploads and other disposable hosting, suggesting an attempt to redirect users to malicious sites. The document body is unreadable, but the presence of numerous unknown URLs strongly supports a phishing or SEO manipulation attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132f9b8632ed---48121244920.pdf In PDF document text
    • http://botosani.ro/img/uploads/file/vasowuvenovunodok.pdfIn PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/gumekijazusirutufemeputeb.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/161305da65b45d---88452370788.pdfIn PDF document text
    • https://sevenhillsgroup.net/ckfinder/userfiles/files/bujipoke.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///46705106410.pdfIn PDF document text
    • http://www.og2c.com/images/file/81164370200.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/75802967843.pdfIn PDF document text
    • http://kyanite.tv/userfiles/file/74800991271.pdfIn PDF document text
    • https://wisserarm.nl/app/webroot/files/userfiles/files/lefomisifijinup.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/aa0da0b4e5cba3e05e26147a9c8eea46/wubuxugimiwagumifoj.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/kovivuzuwibimosas.pdfIn PDF document text
    • http://6nergy.fr/6nergy/sites/default/user/file/kazagaxadejonijurex.pdfIn PDF document text
    • https://gabconstruction.com/ckfinder/userfiles/files/14381241111.pdfIn PDF document text
    • https://www.tristar-technology.com/ckfinder/userfiles/files/faxefarosidaset.pdfIn PDF document text
    • http://loadcell.vn/Images_upload/files/17784297115.pdfIn PDF document text
    • http://dribblebar.pl/userfiles/file/90357211114.pdfIn PDF document text
    • http://tradotel-riviera.com/file/natuwagilafanikozasi.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/161359f17170e9---41475594564.pdfIn PDF document text
    • http://apartmany.cucoriedka.sk/data/files/lojuxutuxese.pdfIn PDF document text
    • http://fmdscu.net/userfiles/file/51742550451.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16132fd5a6aff5---kuzisidafetirob.pdfIn PDF document text
    • http://vinhosnorte.com/images/files/sajisefeburupuvawimakov.pdfIn PDF document text
    • https://jesssmithtri.com/jesssmith/ckfinder/userfiles/files/ranagobol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=introduction+to+phonetics+and+phonology+book+pdfPDF 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_off0000b8a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8A8 15432 bytes
SHA-256: ad7737b4f617cca0a12f73b37e5a78024bcc985674d6624f89af041c88cc525d
font_01_sfnt_off0000dfdc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFDC 11296 bytes
SHA-256: dd612336b8a4bb3a35818c228216181d9b1647c751d801e5b62c2f99166a45c9
font_02_sfnt_off0000f9f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1