Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cd4c7585aeda8d5…

MALICIOUS

PDF

92.0 KB Created: 2021-10-10 02:49:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 60bfcd2901d24ddc6ff157f97d595e6f SHA-1: a601fe3b7f8aae524fc197750b528bd6042c00b0 SHA-256: 3cd4c7585aeda8d512175b90e2d7f3d4b1b2be0ea6ff760c87ef05a5ef7c27ca
120 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, including one that appears to be a compromised WordPress upload. The heuristics indicate a link farm on disposable hosting and a lure related to invoices or payment reminders, suggesting the document's purpose is to trick the user into visiting a malicious site. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 8

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://oniceh.ru/uplcv?utm_term=invoice+payment+reminder+template
    • http://abpjse.news-read.com/upload/files/vufizibi.pdf
    • https://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/vevavakilibeza.pdf
    • https://morethancars.eu/uploads/edytor/file/vobegorugimuwelajinutuv.pdf
    • https://protradingindia.net/userfiles/file/56129522270.pdf
    • http://montaze.org/democms/userfiles/file/24405088927.pdf
    • http://thesei.com/
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/895ea7a28dc1ce86e47fe4316a519c82/96475219016.pdf
    • http://www.polni.si/Images/files/5606939497.pdf
    • http://pop-around.com/file_media/file_image/file/90361695573.pdf
    • http://exima.kr/userData/board/file/83218660582.pdf
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/e470552393fe7f49c4608d116ff4a19a/66770936684.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/u7er6l7uhlaur67vg1oiorq2f9/sufudomonobibed.pdf
    • https://crmsaas.dswip.com/ci/userfiles/files/92648870943.pdf
    • http://golden-candies.ru/webroot/files/files/70781731677.pdf
    • http://midesignvn.com/uploads/files/74294053167.pdf
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/1615a95937ca8d---57434728172.pdf
    • https://ph2020.org/FCKeditor/file/5159696397.pdf
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/15a7rcpapt4lju1llv0tr5jlvo/lewarideve.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/9qvirafb2869hnjt38fdeh2bhv/70236276388.pdf
    • http://ucg-eg.com/userfiles/file/lepob.pdf
    • http://ventiliatoriai.lt/js/ckfinder/userfiles/files/gazubopexudetesadomidola.pdf
    • https://cvzona.lt/resources/img/files/1365409833.pdf
    • 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_off0000fe7e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE7E 16792 bytes
font_01_sfnt_off00011695.bin
133966fedbb95b4743684b880b55979557541b3ec37393bec1b7b6b35da54311
pdf-font-stream PDF embedded font (sfnt) at offset 0x11695 10636 bytes
font_02_sfnt_off00012ee5.bin
a9f20ae3e5c564f36e28414a9dc071c90cb0b46cc1c27ad7e77a685eaadbb802
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EE5 19792 bytes