Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cd3e52c13ec7528…

MALICIOUS

PDF

77.8 KB Created: 2021-08-19 13:11:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1a7e49c255f6afd0d480ce691232f41a SHA-1: 92c6540011c0948bd59b496ba5862c776887247d SHA-256: 9cd3e52c13ec7528b540413bee3e20699c40109c6efeb41e07ede96dc0766883
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. The embedded JavaScript is likely used to facilitate the redirection or download of a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 8

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://irlanc.ru/uplcv?utm_term=grade+1+english+grammar+workbook+pdf PDF link annotation
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/54813909386.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608045cfea873---82145879110.pdfIn PDF document text
    • https://webmenuplus.com/images/file/wijorurimak.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1677b3aa3---diruxezavin.pdfIn PDF document text
    • http://careerpathrecruitment.com/swapscan/app/webroot/js/ckfinder/userfiles/files/66203980391.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160945ccbc0b3b---miruditetotazo.pdfIn PDF document text
    • http://tomasmrazek.cz/userfiles/file/9448323329.pdfIn PDF document text
    • https://a-pointpro.com/cms/ckfinder/userfiles/files/31242245264.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/wuwobolurux.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077450f0381f---91107627829.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/cutma82soq56v2nl68s5qq28r3/57227006551.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/e2903b5a0c5cec5bcb1571227e129c4a/kupebomezot.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160be6cbb44386---nelemuvusabiguzex.pdfIn PDF document text
    • http://stoewebdesign.no/userfiles/file/84988463104.pdfIn PDF document text
    • https://expeditions-travel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e4d379b9ef---57503144934.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160b685a4b6780---10535999224.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bacec739d87---minesul.pdfIn PDF document text
    • http://finpacecuador.com/userfiles/file/45933511080.pdfIn PDF document text
    • https://thewaves.net/wp-content/plugins/super-forms/uploads/php/files/n7ovmg71f1ipavo609cd8vijs4/xewifozuxadoxagutenem.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f21dfac063---sodiminugofezewidez.pdfIn PDF document text
    • http://burnettefamilyreunion2021.com/clients/867108/File/kevosepavopewejetonagewag.pdfIn PDF document text
    • https://habibitoursegypt.com/ckfinder/userfiles/files/39386489097.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5feb1eb93---buxez.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/1607aecc945a16---53320919009.pdfIn PDF document text
    • http://dtpokebar.com/uploads/files/tupifilakaxekafavela.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_off0000cb8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB8C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e3a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A3 11256 bytes
SHA-256: 00673ccb23b1fe502f6a2f4129c4c2abac08d42b18f2fbc13fa5e81aca76a345
font_02_sfnt_off0000fd77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD77 16504 bytes
SHA-256: 8ecb61018798dac6d6fed9e1f21a07de8f7711453d2fff1f542d63034e15a263