Malicious PDF — malware analysis report

Static analysis result for SHA-256 97c00afd6f252e36…

MALICIOUS

PDF

79.6 KB Created: 2021-09-16 02:01:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 36475885c8ab560d6c091cad373d2ef0 SHA-1: 00035b9490bcdb1c8e1faec95d0395160bceaefe SHA-256: 97c00afd6f252e3628a6c68279ccdf1d01e07a2f418b963fd9a152d00e22e75f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, further supporting the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://smidgel.ru/uplcv?utm_term=ookla+speed+apk PDF link annotation
    • https://soudurelauziere.com/upload/editor/file/81980466774.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/kosawatarunavivi.pdfIn PDF document text
    • http://thevale.us/userimages/34421872667.pdfIn PDF document text
    • http://telegid.tv/userfiles/file/turazeju.pdfIn PDF document text
    • http://nguyenthaotech.com/upload/files/88715970166.pdfIn PDF document text
    • http://steinbach.casawell.tw/userfiles/file/terulukiduwo.pdfIn PDF document text
    • https://reklama71.ru/upload_picture/jenodoposi.pdfIn PDF document text
    • https://candbco.com/ckfinder/userfiles/files/burokurepapuzo.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/161403bd302166---28215164905.pdfIn PDF document text
    • http://kfnmdg.com/upfolder/e/files/20210916065053.pdfIn PDF document text
    • http://henghuitong.com/jingkelun/userfiles/files/20210904021212.pdfIn PDF document text
    • https://vinocastillo.hu/editor_up/negijabigifeken.pdfIn PDF document text
    • http://tvtamminhphat.com/uploads/userfiles/file/49484225077.pdfIn PDF document text
    • http://sbsedupatti.com/sbsedupatti/userfiles/file/nanideli.pdfIn PDF document text
    • http://clerus.hu/files/file/37567516756.pdfIn PDF document text
    • http://hiniceshine.com/upload/76379901943.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613079176fc0c---88315305475.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613ce3a9c8b96---nisewabodameg.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/1053b105d29d1e9ff5b84712ebef474d/2254217264.pdfIn PDF document text
    • http://www.elstar.ru/uploads/files/78108710221.pdfIn PDF document text
    • https://viceda.com/userfiles/file/kuzasikugubatasenaxur.pdfIn PDF document text
    • http://yoshitomo-kokubunji.com/jcfiles/file/jazetowafolotibozarixi.pdfIn PDF document text
    • https://deepex.hu/hirek/files/xeribumojadugefesol.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/30573611394.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_off0000d37f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD37F 10108 bytes
SHA-256: f0433b8d50c50422e41876f4f3ffb4ebb6fa9230da84616bd48127a15e41c867
font_01_sfnt_off0000ea2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA2D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001023f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1023F 17932 bytes
SHA-256: 0be96f0f02a75e718a308915069be7e70bcb13aa58d57a0a28d5ded6ed9373d3