Malicious PDF — malware analysis report

Static analysis result for SHA-256 2181e480ee797d5f…

MALICIOUS

PDF

74.0 KB Created: 2021-09-11 23:57:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: a378e7e37b9035ad9624f0167bf729ba SHA-1: 688ff6d06cfea9ca4bbeb9126d2685e2f0937369 SHA-256: 2181e480ee797d5f44cb819ac8cb08b6b2ddc5e0361468751b9814f906814523
164 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload directories, suggesting a link farm designed to distribute malware. The presence of a 'download' button heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://thanaclusterwestgate.leaddeehub.com/userfiles/files/55211890480.pdf In PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/50950111654.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/dikuroguvaradonu.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/16130268e713f5---xadisubonuzimabolebop.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613280fa1a14a---59824192993.pdfIn PDF document text
    • http://korealabels.com/ckfinder/userfiles/files/tigisimutajome.pdfIn PDF document text
    • http://ibb-online.ru/f/file/zufuwuluvazugepef.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/161380e2913102---gekefofe.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133e4b81b39f---serotudikedevibevu.pdfIn PDF document text
    • https://www.stnedu.com/ckfinder/upload/files/30793203206.pdfIn PDF document text
    • http://paitoonbox.com/userfiles/files/telaxewedudasovenuba.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-3/20210903011754365529.pdfIn PDF document text
    • http://sacmacbook.net/userfiles/file/ladavava.pdfIn PDF document text
    • http://asckhn.com/acskhn/userfiles/file/41779975642.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130c5bd5c82e---1669484051.pdfIn PDF document text
    • http://nilesk.com/userfiles/file/56211991134.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/8dccb58815d6d3393d187a583b03d425/22692113827.pdfIn PDF document text
    • https://latework.cz/soubory/1294375428.pdfIn PDF document text
    • http://architettogherardi.eu/userfiles/files/9502020925.pdfIn PDF document text
    • http://belly.bpv.su/content/files/files/50875695943.pdfIn PDF document text
    • http://akicgiyim.com/userfiles/file/76297042449.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161383915b4a3d---revasokepavujizix.pdfIn PDF document text
    • https://campermagazine.tv/public/file/8449980195.pdfIn PDF document text
    • https://macroedunet.com/userfiles/file/87913877805.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613923f3d51aa---muvisivolexunuxoredawigog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=pokemon+let%27s+go+pikachu+download+apk+androidPDF 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_off0000bd2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD2E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d545.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD545 11276 bytes
SHA-256: 0550aff71e7800b4a46e4b0136e2c3aa2fe9465ded11640d01c4265fec3ebf16
font_02_sfnt_off0000ef78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF78 16564 bytes
SHA-256: 5ee7df70071d5f0e977fe457b23f32e53d9535c769e9fcf6c870a4d45825cb2c