Malicious PDF — malware analysis report

Static analysis result for SHA-256 deffc4e4d482ecbe…

MALICIOUS

PDF

69.4 KB Created: 2021-09-26 00:47:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 6132ef7f3864302380f4c75e89edf55b SHA-1: 976c18a33ad50332bb6f7960d6171dc623839de1 SHA-256: deffc4e4d482ecbecf10b2f67a69aa4186502a9329eb70b657d4a6480d4d2740
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the structure and embedded links suggest an attempt to direct users to malicious content or phishing sites, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 5

  • 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://perilatomsk.ru/ckfinder/userfiles/files/67243054004.pdf In PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16143122c3138e---3469229448.pdfIn PDF document text
    • http://ryukatsu.com/userData/board/file/bolobazodo.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/n0p4p27o1tcmnjl1qscqdjpil5/40139688827.pdfIn PDF document text
    • http://linyuepharm.com/upload/files/moleb.pdfIn PDF document text
    • http://cheniou.handysociality.com/upload/files/88788516848.pdfIn PDF document text
    • http://fijiembajak.com/uploads/ck_uploads/files/90901995491.pdfIn PDF document text
    • https://mimpishio2.net/contents/files/kigoxagopumodejivamuna.pdfIn PDF document text
    • https://art-gallery.mn/uploads/files/56344607645.pdfIn PDF document text
    • http://diennuocdanang.com/uploads/image/files/fodokexibowobofesoxonile.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/laxinifinekojoluvelat.pdfIn PDF document text
    • https://quatden.vn/webroot/img/files/87308559566.pdfIn PDF document text
    • https://artbynela.com/uploads/file/39578961352.pdfIn PDF document text
    • http://anticacarsulaeborzoi.eu/userfiles/files/zofonisokexegaje.pdfIn PDF document text
    • https://gemma.lucien-sv.info/uploads/files/614f8e661fc26.pdfIn PDF document text
    • http://abimobiliare.pl/pliki/File/13282486452.pdfIn PDF document text
    • https://wisestudentz.com/userfiles/file/mefam.pdfIn PDF document text
    • http://iccjsc.vn/images/uploads/files/kowakadiset.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1613ef6f65c6b5---gikolipavi.pdfIn PDF document text
    • http://ghefootmassage.com/fckeditor_userfiles/file/15744383819.pdfIn PDF document text
    • https://98ing.com/upload/ck/files/20210912_163744.pdfIn PDF document text
    • https://gemwares.com/userfiles/file/bozinowaxobovubijunuf.pdfIn PDF document text
    • https://basisnomor.com/contents/files/femovisazulogegoxesinazes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=gunship+strike+3d+hack+apkPDF 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_off0000b114.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB114 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c92b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC92B 10848 bytes
SHA-256: 32bd0f0af87ce9fb1915860ccad779d60f2d788ebfb73b40ac6c95aa2626c445
font_02_sfnt_off0000e234.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE234 14908 bytes
SHA-256: 6843e67c1c75ca50ca774402679b5c67c46071dc5bc2da7db92667d3530efb84