Malicious PDF — malware analysis report

Static analysis result for SHA-256 66945ac5fe9cd7da…

MALICIOUS

PDF

85.1 KB Created: 2021-09-17 14:48:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 74ae4fd6aedd243b83da34c8662357c6 SHA-1: 1b2a7ba8d7dd6e173c0b1d4ce236e30d0d66aaee SHA-256: 66945ac5fe9cd7da09de889c2479d81d76ee3ba56f2ca8f34dd3c54f594e63a4
156 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics as a link farm and a potential phishing or trojan delivery mechanism. The ML classifier and ClamAV detection strongly indicate malicious intent. The numerous embedded URLs, many hosted on compromised or disposable domains, are indicative of an attempt to redirect users to malicious content, likely for credential harvesting or further malware deployment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://muzycznescyzoryki.pl/userfiles/file/28265815683.pdf In PDF document text
    • http://www.gonouvellezelande.com/files/46530976460.pdfIn PDF document text
    • http://osteriailgalloelinnamorata.com/userfiles/files/wudevemajovuv.pdfIn PDF document text
    • http://tomekorea.com/userData/board/file/39308918622.pdfIn PDF document text
    • http://tianfonmm.com/d/files/78780747847.pdfIn PDF document text
    • http://myhoteltrip.com/userfiles/file/rilobobigapoxixaj.pdfIn PDF document text
    • http://kredoteka.ru/uploads/file/53480617289.pdfIn PDF document text
    • http://bamboomfi.com/htdocs/cljr/data/files/wavana.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/82ji714sq93fv7p4g8bu1omekc/77560693862.pdfIn PDF document text
    • http://degrossier.nl/uploads/file/86544114749.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/i06sj7flifjihb384qovnirnqo/83970119383.pdfIn PDF document text
    • https://eirai.org/editor/ckfinder/userfiles/files/xefel.pdfIn PDF document text
    • http://dispensapertutti.com/userfiles/files/berurirudewi.pdfIn PDF document text
    • http://knshzj.com/CKEdit/upload/files/76495542804.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/t20hbvlrck5raud9quq9iiiec3/vaxugavarababopuxufeb.pdfIn PDF document text
    • https://open-call.fr/uploaded/files/96238028292.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/78049290754.pdfIn PDF document text
    • http://xn--b1agaa2anfqdp.xn--p1ai/ckfinder/userfiles/files/mumedorobodositolufirodav.pdfIn PDF document text
    • https://mamap.in/ci/userfiles/files/fofajolekijasebonema.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/a910deec675932dd3d705b4a20e67017/4876847955.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=free+fire+theme+for+androidPDF 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_off0000e573.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE573 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD8A 10384 bytes
SHA-256: c79e335956fa9f5b12732157ed631549756bff3bb89febee5c6bcd6c2070572e
font_02_sfnt_off000114c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114C5 19216 bytes
SHA-256: ebd93d0b1fe400920e437437548645570d3f5b47ba966097456f030773ddcb55