Malicious PDF — malware analysis report

Static analysis result for SHA-256 e532c9572ea2996b…

MALICIOUS

PDF

80.0 KB Created: 2021-09-13 12:24:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 37a81435d2894ebebbfa2a7ba4ae3780 SHA-1: 26b8e549ad74d50a477014ba8c23c1511e1432d9 SHA-256: e532c9572ea2996ba413c88b6bf4937f37635a8b78688eecbf275bd8788a2d56
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous embedded URLs pointing to other PDF files. Several heuristics indicate this is a link farm on disposable or compromised hosting, designed to distribute content or potentially malicious files. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these linked documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://markjfox.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/93843226070.pdf In PDF document text
    • http://byecook.com/ckupload/files/gedub.pdfIn PDF document text
    • https://oglethorpeclub.org/~oglethor/UserFiles/file/nawuronerunizezubugosex.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131ad7521353---93552487337.pdfIn PDF document text
    • http://tiquital.com/documentos/file/2706780179.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/161304ab006318---nubife.pdfIn PDF document text
    • http://lamay.de/userfiles/file/87293326741.pdfIn PDF document text
    • https://vinocastillo.hu/editor_up/56211980892.pdfIn PDF document text
    • http://clubselectionvoyages.net/images/file/mivepinubupegawutaj.pdfIn PDF document text
    • http://shceping.com/upFile/photos/2021-9/file/kefaxepasakoseku.pdfIn PDF document text
    • https://gencatakan.com/upload/file/28295379572.pdfIn PDF document text
    • https://rarahil.org.np/ckfinder/userfiles/files/vigim.pdfIn PDF document text
    • http://jawarakreasi.com/file/67460934869.pdfIn PDF document text
    • https://dreamscapes.ca/dream_scapes/userfiles/files/fisedewi.pdfIn PDF document text
    • http://omnoiptv.com/outscapes/admin/ckeditor/uploads/ck/files/75008248148.pdfIn PDF document text
    • http://bon-mar.com/fck_user_files/file/42568445933.pdfIn PDF document text
    • http://hockjoohin.com/admin/uploads/file/9178156370.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613d6152df77d---vivisotoj.pdfIn PDF document text
    • http://www.rafaellucenaehijos.com/ckfinder/userfiles/files/88872362898.pdfIn PDF document text
    • https://duproject.com/uploadEditor/files/lopudulibedew.pdfIn PDF document text
    • http://girc.ncue.edu.tw/ckfinder/ckfiles/files/5526781214.pdfIn PDF document text
    • http://dienmaythanglong.org/uploads/files/71994552591.pdfIn PDF document text
    • http://studiostocchi.eu/userfiles/files/96008553023.pdfIn PDF document text
    • https://playworkspartnership.ca/sites/default/files/file/41885229919.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=american+physics+teacherPDF 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_off0000d656.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD656 17356 bytes
SHA-256: f84c91e34b1d8a1cbf5fcefacccfacb08dbe52dbf89acb54cfcf6dd7e4d8fa92
font_01_sfnt_off000102d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D5 10568 bytes
SHA-256: 1fbb98ef5f9a0a42dfb99bfbf5f94f89108b40eba9f432d4d44e05450561c6f2
font_02_sfnt_off00011ac6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AC6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1