Malicious PDF — malware analysis report

Static analysis result for SHA-256 cadad3da5b076e94…

MALICIOUS

PDF

77.0 KB Created: 2021-09-19 13:47:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 75e5319d2e0f78ca81b4ab7b8b35f023 SHA-1: 91f009d77015b00b151154475dd1d6d8cc7396f9 SHA-256: cadad3da5b076e94a5954c7c4d222b77c46b00c5a74ce780d59d127c3a5ab6d1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating it is a link farm hosted on compromised CMS upload storage, designed to redirect users to other sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the structure and URL patterns are indicative of a malicious document.

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 https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16142a4accfbbf---45985063859.pdf In PDF document text
    • http://gutachterbewertung.de/userfiles/file/48492723715.pdfIn PDF document text
    • http://homeopathyhongkong.org/files/47679626597.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613463c9a57da---71576683116.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/99001700722.pdfIn PDF document text
    • https://kalimati.in/userfiles/file/watowixezoraja.pdfIn PDF document text
    • https://istanajpdua.com/contents/files/53889933340.pdfIn PDF document text
    • https://nayyaralidada.net/alpha/ckfinder/userfiles/files/fabuko.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/161324c0d1c809---nudulawifuripijefiwupi.pdfIn PDF document text
    • http://missteenqueenuk.com/userfiles/file/49597614785.pdfIn PDF document text
    • http://spielundlicht.de/content_provider/documents/files/88788058590.pdfIn PDF document text
    • http://dietmoiquangle.com/webroot/img/files/56953465257.pdfIn PDF document text
    • http://kawana.tech/userfiles/file/lokuzixi.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613af3fcf3db3---86991119581.pdfIn PDF document text
    • https://imotrading.com/images/userfiles/59044868887.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021091400445315.pdfIn PDF document text
    • http://npcbalkan.net/ckeditor/ckfinder/userfiles/files/29501142706.pdfIn PDF document text
    • https://www.huaikrachaohospital.go.th/assets/global/lib/ckfinder/userfiles/files/58393831128.pdfIn PDF document text
    • http://www.fdconsult.qa/public/uploads/cms_files/91209358035.pdfIn PDF document text
    • https://sukaunited4d.vip/contents/files/16703494405.pdfIn PDF document text
    • http://tomgiongvip.com/uploads/files/file/begusaj.pdfIn PDF document text
    • http://nfc.soo.jp/file/majusaxuv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=some+pattern+lockPDF 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_off0000cc1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC1E 16496 bytes
SHA-256: a04024058e5f84653aa2861e8664d37662259deed72daacd4c853798a5f31d11
font_01_sfnt_off0000f6d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6D7 10444 bytes
SHA-256: da2a2c3a735c5913168d0ace3d74551b51185db2d2689465f97062c16eb44da2
font_02_sfnt_off00010e89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E89 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1