Malicious PDF — malware analysis report

Static analysis result for SHA-256 a56c4dad22d77c52…

MALICIOUS

PDF

76.9 KB Created: 2021-09-02 05:13:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9d150757d3a9133d1d0feb09c592836a SHA-1: 166e3f828d35059097426ab2f14e9eae2437b3ca SHA-256: a56c4dad22d77c523476213bd3e6751a767b615368d92d4dc1c5ee846dd7ee5a
164 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 or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious sites, which are designed to host further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • 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.
  • 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.
  • 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://irepairplus.nl/app/webroot/files/userfiles/files/judenukew.pdf In PDF document text
    • https://xn--faades-mtal-n9a6a.ch/ckfinder/userfiles/files/91413674482.pdfIn PDF document text
    • http://expertcomptablecourreges.fr/michel_courreges/userfiles/file/22650049713.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/46517454332.pdfIn PDF document text
    • http://divorce-difficile.fr/userfiles/file/wudokikanavogetomufupuf.pdfIn PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/87277370721.pdfIn PDF document text
    • http://www.apsetedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f46ce692f9---xemode.pdfIn PDF document text
    • https://matras-matrasych96.ru/admin/ckfinder/userfiles/files/lipixikiranudutebi.pdfIn PDF document text
    • http://lamekatus.ee/uploads/ckeditor/files/62133037641.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c31c1bf7f2---tudiji.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/96069165344.pdfIn PDF document text
    • http://sanders-scottfamily.com/clients/26926/File/30742981646.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607636328a621---pamaton.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/791d6dc11fe736c5a46f38cc802cde1e/83506453037.pdfIn PDF document text
    • http://suapaiatuipelehakefamily.com/clients/80707/File/wefus.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/pomekalulazoj.pdfIn PDF document text
    • http://lahma.pl/_u/userfiles/file/rapupisitanokudafigubenef.pdfIn PDF document text
    • https://flcevent.fcu.edu.tw/plugin/ce1/ckfinder/userfiles/files/20210820232654.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1609fd7fe50f8c---22101047341.pdfIn PDF document text
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/3f1200122c3885e3ef9699f8deccbf61/tekavom.pdfIn PDF document text
    • http://akiyastyle.com/app/webroot/js/ckfinder/userfiles/files/kijudivafatoronumimawaroz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=paying+my+duesPDF 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_off0000ca38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA38 17144 bytes
SHA-256: 26e8badc252730223d2b148308a759bd26875099a50bdd6072355349d1e4fa72
font_01_sfnt_off0000f6c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010edf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EDF 10440 bytes
SHA-256: 21d9df94b04936d9c40dc0e0aecf10ca9433a3bb564ee5494d3da851678e3686