Malicious PDF — malware analysis report

Static analysis result for SHA-256 05d90c50fed70c42…

MALICIOUS

PDF

119.1 KB Created: 2021-07-25 18:01:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 937d72da671ca6248f9643d528d1f314 SHA-1: 788537b90157bd2e4849024ea8e6065c4a744a4f SHA-256: 05d90c50fed70c4214629706e7aa11b48b3a8aaa295ff6ec1fd406ee2f110da6
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress upload directories and disposable hosting, suggesting a link farm used for phishing or malware distribution. The PDF structure and link farm behavior align with common techniques for initial access via spearphishing attachments.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9885

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://omegaplus.bg/uploads/pages/files/revexawuvibi.pdf In PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/51202905063.pdfIn PDF document text
    • http://ok-poland.com/userfiles/file/tabaxutuje.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/ecae621d67f6d9f5f05c3d8b796a5187/pirebojomibex.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/6110ac3805b595ca54eee8c1798ff217/givutazunoxa.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/jabekirotototofoxinaredub.pdfIn PDF document text
    • http://ibb-online.ru/f/file/20153647438.pdfIn PDF document text
    • https://frontlinetherapist.com/wp-content/plugins/super-forms/uploads/php/files/e4ee23763300a1cc3857006ca82cb114/92892384691.pdfIn PDF document text
    • http://forter.vn/hinhanh/file/zuwuba.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/16092a460e41ef---mimasobota.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c682b2683d9---kefudakin.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/70182924871.pdfIn PDF document text
    • https://gea99.com/ckfinder/userfiles/files/tasivokuxedezitiv.pdfIn PDF document text
    • http://xn--b1akwe.xn--p1ai/userfiles/file/32825644766.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b470bf316eb---kibetizi.pdfIn PDF document text
    • http://altinay-law.com/images/file/dunezifinawododuxug.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/p9o47faat8e20m8802u6tllid4/potisosegof.pdfIn PDF document text
    • http://hrudolf.com/userfiles/57027755517.pdfIn PDF document text
    • https://bamor.org/userfiles/file/89473998106.pdfIn PDF document text
    • https://office-agglo-larochelle.fr/userfiles/file/zerizudenovefezali.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb3d2ab7278---sunowuwefiwasekifoxovir.pdfIn PDF document text
    • http://studiolegalezullo.eu/userfiles/files/82271399261.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081fc00bada0---77109698599.pdfIn PDF document text
    • https://innovaciones-plasticas.com/imagenes_cont/sitio/documentos/49285736896.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/5f3a96df8b6522201ed86218b2e18138/90696729932.pdfIn PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/817f37d13ba94c479162e63979612d40/zeneraxukere.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=toni+morrison+short+story+recitatif+pdfPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f01b323baf7---difebopulabej.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_off00016e6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16E6C 10916 bytes
SHA-256: 37b4047822efc000ec0fcb830dd671b0db1bb09414333b8f8af995ec67860935
font_01_sfnt_off0001878b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1878B 17092 bytes
SHA-256: 16f09f50451e454bc0c714d756ea1b831b01adf59a3780bc150031ed9f356f09
font_02_sfnt_off0001b464.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B464 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1