Malicious PDF — malware analysis report

Static analysis result for SHA-256 36db6b3461526f8a…

MALICIOUS

PDF

74.1 KB Created: 2021-09-27 08:54:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: a163256f70f0fe0f3111b4df6c92556b SHA-1: 5d0002388847d9e634effadd28d265ad6d821ec3 SHA-256: 36db6b3461526f8a0df046fd5391486c5c08b088fd703aa341c8b2052eb64c6f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised CMS upload directories and disposable hosting, indicating a link farm or SEO spamming operation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://nuovartea.eu/userfiles/files/tazesupolobiwiden.pdf In PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/q3k59e24sqf9ki8e91a115hr3i/43407908036.pdfIn PDF document text
    • https://efficientinfocomm.com/ckfinder/userfiles/files/9072509073.pdfIn PDF document text
    • https://vetregistr.com/ckfinder/userfiles/files/84562111309.pdfIn PDF document text
    • http://ideal-site.ru/userfiles/file/dobugiforelumagug.pdfIn PDF document text
    • http://medigroupvn.com/upload/files/84570968002.pdfIn PDF document text
    • http://gemmacapitalgroup.com/foto/file/loguteka.pdfIn PDF document text
    • http://sissonne.hu/editor_up/xipusos.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/u5olseb5masag4n2280va9raf5/55108648837.pdfIn PDF document text
    • http://suchanekstomatolog.pl/files/file/jogebowivav.pdfIn PDF document text
    • https://showdetango.com/bafa/userfiles/file/woniba.pdfIn PDF document text
    • https://cli-kh.com/uploads/files/202109170546362812.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/jolokitopofuvet.pdfIn PDF document text
    • http://xinxinhouseware.com/uploadfile/files/taribadum.pdfIn PDF document text
    • http://hzeiger.com/userfiles/file/52050394874.pdfIn PDF document text
    • https://truckforceone.eu/upload/editor/file/45356736107.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb21c71518---28164112835.pdfIn PDF document text
    • http://preiss.at/upload_files/files/87679937618.pdfIn PDF document text
    • http://net-work.cz/data/file/jivujoxowiduxevedeweto.pdfIn PDF document text
    • http://livelyway.com/ckfinder/userfiles/files/36975353033.pdfIn PDF document text
    • https://floraplant.gr/FCKeditor/userimages/file/wibewirenanetotala.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e076ce8bfa---vasalo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=unblocked+games+madalin+stunt+cars+3PDF 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_off0000b700.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB700 19016 bytes
SHA-256: 1f51633290032ee27d7c1bf6eeca86eb4bc8ccd5187ef5e21004a0a067c25cc1
font_01_sfnt_off0000e891.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE891 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000100a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100A8 11224 bytes
SHA-256: ab4ef1b5cbdd5f19e2715059ccfab08a2ef6be44049b15dd60571a1e448fc668