Malicious PDF — malware analysis report

Static analysis result for SHA-256 39f9d509d65e241e…

MALICIOUS

PDF

84.7 KB Created: 2021-06-26 09:06:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0444d611fef38a85f59cb1835b1fef79 SHA-1: a579678cbc8c8226c69e046a765a9ffe75d07aea SHA-256: 39f9d509d65e241efdd9402bbbaf6576593e3a2e6cfc0e6e1f885a1d0fb633e9
172 Risk Score

Malware Insights

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

This PDF file contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving the execution of a second-stage payload via the embedded JavaScript.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://pistant.ru/uplcv?utm_term=online+pdf+editor+software+free+download
    • http://xlsferrosilicon.com/d/files/sazisirolirusotowu.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b8c3afa3364---73090294910.pdf
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/9a8c1a72fe9ebba3798e7408845464ae/namitamav.pdf
    • http://www.almansori-ye.com/almansorifiles/files/nolijek.pdf
    • https://etonbio.com/newsLetters/images/file/dijogikab.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b08ec9a5ab4---81804589584.pdf
    • https://andrejc.si/files/file/53768948996.pdf
    • http://hiace-yoshikawa.com/js/upload/files/regifekozafuku.pdf
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea5258cbd4---72745142545.pdf
    • http://hotechike.com/files/files/19186430123.pdf
    • http://vimbark.sk/editor_uploads/files/nofegowidopurodafa.pdf
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080868545007---59484913805.pdf
    • https://stopserv.ru/files/file/62904747718.pdf
    • http://kusadasidentalclinic.com/img/userfiles/files/904840133.pdf
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/mcrc3u8nill7opvg2qbma83m0r/xiredarutikatujom.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc4f0cbdbb---sixumilibivotitekirulov.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a343c89f989---72175135107.pdf
    • https://transpack-krumbach.de/_upload_bilder/_filemanager/file/xexusokowazokemipor.pdf
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/jvuhl8h3tpkl6e41jav6p6mndh/jibabigixafobizezi.pdf
    • http://sbs-group.co/userfiles/files/jufuko.pdf
    • http://sztarmedia.hu/_user/file/14574136.pdf
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160984c3dcf639---ruzovumutovexavurifodewun.pdf
    • https://www.lightingsolutionsinc.net/wp-content/plugins/super-forms/uploads/php/files/9292f801d86ab9bd4217e27290497221/68569333429.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7b4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7B4 16792 bytes
font_01_sfnt_off0000ffcb.bin
7ec4facac320942c86dbc5a2f2d763c52522a818ed48ccaa77af222255c58f70
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFCB 10604 bytes
font_02_sfnt_off00011832.bin
606fef34fa5cccc70d072545d9ff41ea5ee5808d9ef09f381f05d030921bc9d9
pdf-font-stream PDF embedded font (sfnt) at offset 0x11832 17380 bytes