Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a433c3ca73a968a…

MALICIOUS

PDF

82.2 KB Created: 2021-09-02 12:29:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 1cfce91fe495acfba67bebf096672775 SHA-1: 2d63107b72e80992e962c78ca18454ce460f22b4 SHA-256: 4a433c3ca73a968a1aba7a14a031f354e520e5593bbb2095ed18aeb93d0ac9d2
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to other PDF files hosted on compromised websites, indicating a link farm designed to obscure the ultimate destination. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of multiple compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/6706828e33fb71734944f5dae4a9ba89/43663613213.pdf In PDF document text
    • https://aildf.in/userfiles/file/nazirugewibi.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-5-24/20210524030137997396.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-4-30/20210430101604203608.pdfIn PDF document text
    • https://aldurra.ly/images-editeur/img/file/85051114628.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1609e41afb0c0a---ditekusexodefiwu.pdfIn PDF document text
    • http://zwickerfoto.hu/_user/file/malogaduboxajipemew.pdfIn PDF document text
    • http://ttmplus.com/userfiles/files/bosorafadaje.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a02728cc1f5---74516137024.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/72126615983.pdfIn PDF document text
    • http://gyogytornasziget.hu/uploads/files/15512345721.pdfIn PDF document text
    • https://adasms.fr/userfiles/file/87482940258.pdfIn PDF document text
    • http://dientrotiendathc.com/media/ftp/file/50514511406.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/a49a3b05d7c95841321eb64c619e9fb9/21159396031.pdfIn PDF document text
    • http://shoreluxurylimos.com/userfiles/files/19901940658.pdfIn PDF document text
    • https://kga-am-adlergestell-ev.de/kga/ckfinder/userfiles/files/zomonedimibedom.pdfIn PDF document text
    • https://efficientinfocomm.com/ckfinder/userfiles/files/6949858022.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2eeca236f0---kejesarojewulavurajim.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160c5d377bb209---sibafefewezesijasegedu.pdfIn PDF document text
    • https://bestwaynepaltrek.com/ckfinder/userfiles/files/voxudopa.pdfIn PDF document text
    • http://vietnam-intraco.com/webroot/img/files/mumawoxexegewilanije.pdfIn PDF document text
    • http://holidayinntorino.com/userfiles/files/kafitagelarevisi.pdfIn PDF document text
    • http://tylincms.com/userfiles/files/kevoforonapizux.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/e025f3a5c58eb53548c26a4ce6bb6295/gebanakazolabu.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/16085c066d173c---21611402343.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607da894500f9---judegeviseserujetu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=msci+esg+index+pdfPDF link annotation
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/13ee662fd0bc65bcc3a3680f946e421e/xegabexobomep.pdfIn 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://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_off0000ddea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDEA 17548 bytes
SHA-256: bce0d9a47546a1fb99cf343dcc164498a7242c91caf1b68b124b93c3ffacf041
font_01_sfnt_off00010baf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000123c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123C6 10364 bytes
SHA-256: ee7fa479fb3b42a605de1e9739d1544d866f8cb1dc45096230d74ab20d33cc1e