Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c20343bfd7ff995…

MALICIOUS

PDF

69.0 KB Created: 2021-09-28 03:59:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 0900f8afc295a2b823d2277a23c6d384 SHA-1: b0c723c060bbad3a5733abd7ff566fc6d330eac9 SHA-256: 9c20343bfd7ff995f2a7acb52b8b3d9ccc7b7871922d523e870693e465388204
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a downloader or redirector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kedehg.com/ckfinder/userfiles/files/72501375083.pdf In PDF document text
    • http://intranet.uts.edu.co/portal/app/ckfinder/userfiles/files/99723900333.pdfIn PDF document text
    • https://mantyobras.com/userfiles/file/woxulazovonetivegogejegu.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614e34d4512bf---16020603421.pdfIn PDF document text
    • https://childprotectionindia.com/lexcyberia/userfiles/files/36590903833.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109140427084298.pdfIn PDF document text
    • https://bike-accessories.supersites.gr/content/ckfinder/files/59975563364.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1614d0b5f0e4bf---fejifuw.pdfIn PDF document text
    • https://ocw.tw/uploads/files/tufusuwavu.pdfIn PDF document text
    • http://hujiangsy.com/upload/files/58335847227.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613719e4c91d9---69526475141.pdfIn PDF document text
    • https://sanvexe.vn/webroot/img/files/rusepu.pdfIn PDF document text
    • https://cargobull.cz/res/file/miker.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614ff82d2d51d---bigonajakinowanavajaretow.pdfIn PDF document text
    • http://dagmar-e.de/userfiles/file/gorariga.pdfIn PDF document text
    • https://maritime-models.com/userfiles/file/67167758902.pdfIn PDF document text
    • http://mitsubishilongbien.vn/images/ckeditor/files/70869550020.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614121ed7ca9d---kijiralepuvipobaj.pdfIn PDF document text
    • http://konditsionery-reutov.ru/upload_picture/file/22310652882.pdfIn PDF document text
    • http://teacherandtraining.com/coj_u/KK/userfiles/files/63508604780.pdfIn PDF document text
    • http://ventexevent.se/uploads/file/12716600226.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16145cf1887557---46715779596.pdfIn PDF document text
    • https://dreamscapes.ca/dream_scapes/userfiles/files/67138980861.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=square+root+of+7+isPDF 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_off0000afb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7CA 15416 bytes
SHA-256: 1eaac35e5eb162bc66353011f950d2171707cc2d0741f52db2c12e9fc15b6afd
font_02_sfnt_off0000eef6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF6 10428 bytes
SHA-256: 85f840b84a68f0f4813e300deab23d8648e7fd4a3a9e60f2eab23d5f72e1a92f