Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c5a0e8603c875f3…

MALICIOUS

PDF

83.0 KB Created: 2021-09-02 01:53:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 81843b141ed244b162a372d591856a87 SHA-1: 31b1f7590078ae775d7aa3b789b290737dd2ab1b SHA-256: 2c5a0e8603c875f3e8f4987cbf12ecc9837e0fb5ca61c64a743c8f5da7b3bd8f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating it's a phishing or trojan PDF. It functions as a link farm, hosting numerous PDFs on compromised WordPress sites, likely to distribute further malicious content or phish users. The presence of external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16128faa217f24---likiv.pdf In PDF document text
    • http://studiodabo.eu/userfiles/files/6728704955.pdfIn PDF document text
    • https://www.stjohnhomelessshelter.org/wp-content/plugins/super-forms/uploads/php/files/7ff823430f1e2221fd47e46489343a2e/59848720541.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac178ed0603---52926771371.pdfIn PDF document text
    • https://ltssinternational.com/res/wysiwyg/file/90591828099.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/7aoj8g2d55f808b28hljl5uk90/letagide.pdfIn PDF document text
    • http://tizianaiberti.it/userfiles/files/dijasofazasolo.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/fa72c83070cd5d6a75dd4b836cd4d594/76023296417.pdfIn PDF document text
    • http://herculesestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/1333013682.pdfIn PDF document text
    • http://ourdesign.hk/ckfinder/userfiles/files/36315295168.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/3f16cef2df3a2ee4bb6e968a2c97193b/98445978794.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad1e8c3ed28---raguxatuwaranaxof.pdfIn PDF document text
    • http://nessium.fr/userfiles/file/30733888045.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/2490591430.pdfIn PDF document text
    • http://booklandbooks.com/userfiles/file/44885625686.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea026622d1---9423666423.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/55192211671.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a548c67da89---foxesuritopifu.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/100becccb1db3f800dd3c2ece954b9ea/59286336759.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/5f10a9e1e6854b38f595223021c5dbf2/jazipijarexenizeseb.pdfIn PDF document text
    • http://blackshirts1960.com/clients/876325/File/saravumadorugawovefera.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/38jjifle6nsk1tkt7dn1n7t9l5/34124733931.pdfIn PDF document text
    • http://synagoge-stommeln.de/ckfinder/userfiles/files/joxunovijanezibuziraj.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16092ccf1a0d26---41541828651.pdfIn PDF document text
    • http://dintainoodle.com/uploads/files/mofawekasodutodapudu.pdfIn PDF document text
    • http://moriefrusca.com/userfiles/files/1303704241.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=without+holding+taxPDF 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_off0000e182.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE182 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f999.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF999 10324 bytes
SHA-256: a15dd8b2acbd5bbeff50811c978fa7cfa23ba0854d818d47d5c14bc0440492ec
font_02_sfnt_off0001108f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1108F 17092 bytes
SHA-256: e407061ee2a8be43c8b3c0c1e786012105a723544b3a1ceff154d15e1d3af616