Malicious PDF — malware analysis report

Static analysis result for SHA-256 2db63632db517a13…

MALICIOUS

PDF

81.3 KB Created: 2021-08-27 18:05:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 270ed6e2dddb41df2dae2665032961b8 SHA-1: 84629964dfb9cb86cb3696b0ecf55b448bcbd068 SHA-256: 2db63632db517a13c9e89793f34eef08e49b5d16ab0e90b08232e6b35cebfdbe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous external links, including one pointing to a compromised WordPress upload directory, suggesting it's part of a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://fivetc.vn/uploads/files/69662212663.pdf
    • http://nadiadsa.org/userfiles/file/mukavovavaw.pdf
    • https://silga.ca/userfiles/file/resufofi.pdf
    • https://sahodayabbsr.com/test/fckeditor/file/91854462823.pdf
    • http://softtox.com/new/userfiles/file/wowuselutufimomiborok.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/a2a779500dbb24265603845f9da18f1e/xigurewonaf.pdf
    • https://toptenstudy.com/upload/files/BodyFile__611D5EDC9D6A7.pdf
    • https://sieuthimaytinhcu.vn/upload/files/xorapubowagudu.pdf
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6e133d4746---25395546134.pdf
    • http://adaviestransportltd.com/userfiles/file/waxawovifip.pdf
    • http://oshcongregation.com/userfiles/file/giwuweboriteralegasono.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/a3f51oaahcncmaggjed9imjk26/zuxogifiwidamuladesigoxi.pdf
    • http://hiroi-es.info/yamituki-n/uploads/files/67878795826.pdf
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/985c63811a91148a881103e1f5d00237/potajeg.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1d3c4cf395---59591078911.pdf
    • http://leasingtowers.com/ckfinder/userfiles/files/90518534884.pdf
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16073f09046b90---pevonodudip.pdf
    • https://stmarys-perthamboy.com/upload/File/dudemevifeteganesadesux.pdf
    • http://www.iciparis.ru/ckfinder/userfiles/files/97309146621.pdf
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/86c4a06054c5a1876e56d6efa0da82e6/15628559129.pdf
    • https://adamant54.ru/userfiles/files/zowiworebi.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c239864c4b4---pubewopabemal.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=the+purloined+letter+short+summary
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d64f.bin
077f9dd0d98637e81e3e6630b5b1097d0cdaabd973d71bfb3fdf02e33e918b8a
pdf-font-stream PDF embedded font (sfnt) at offset 0xD64F 18432 bytes
font_01_sfnt_off0001061f.bin
ef1f8c50e12da68951eef2b7d2e951caa9692bf31595a3a11e5c638789d1060b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1061F 10836 bytes
font_02_sfnt_off00011eec.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11EEC 16792 bytes