Malicious PDF — malware analysis report

Static analysis result for SHA-256 23c4f168e0903218…

MALICIOUS

PDF

87.0 KB Created: 2021-07-15 19:36:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9cdb68195b3d1150d2ebf0cde3d7cdd0 SHA-1: 728b92272aba216276b9651b2d60279d0191e8f5 SHA-256: 23c4f168e09032182c821f1190b6c03ebdebdfd997deb3ec7237fe749b2a3da9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised WordPress sites. One URL is specifically identified as a link farm on disposable hosting, suggesting an attempt to obscure the true destination or host malicious content. While no scripts were directly extracted, the nature of the URLs and the ClamAV detection strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0e82d14153---90916551790.pdf
    • http://moda-minulosti.cz/docs/momin/file/ragikuguletorefadiz.pdf
    • http://onnetsolution.in/userfiles/file/35193342658.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bccebea69fd---rumotuni.pdf
    • http://notarbrazda.cz/userfiles/file/jegixigalesesumij.pdf
    • http://tanriovermensucat.com/uploads/genel/files/44763111347.pdf
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/8bc400d35dcb088c97a0c01dafe4c7e3/lodexofeki.pdf
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090896712b56---64137383209.pdf
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/48b275d3c0092d3949a491b6556ff2de/40533418648.pdf
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609a3080d5b91---zirununamadamokulaforamo.pdf
    • https://cecprint.com/images/file/85122348803.pdf
    • http://wwpokebar.com/uploads/files/57978684072.pdf
    • http://greer2001.com/clients/e/ea/ea56749d84c1a2d7db36d2c51c833a37/File/8589319336.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bacb483f5d---46241533939.pdf
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b29afd930aa---13541081478.pdf
    • http://bualuang101.com/backoffice/upload/files/kofazekugafipodabaza.pdf
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/794c2f2f7a669a37f1cdd68f5fb8e7ee/91359551535.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160aaf74d0e298---69892676530.pdf
    • https://123natura.com/stockages/files/nekofibi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=marilyn+mccoo+one+less+bell+to+answer
    • 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_off0000f0b1.bin
cd368a14327e5cd3da77a1c2088f94afa126bc1ef5f8c917ee9e4e6bd439d5c4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B1 17544 bytes
font_01_sfnt_off00011e5f.bin
0738b0bad2739a6e4ea71eab719b19dabf466c62538cb71819ad884937f7c2ba
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E5F 10724 bytes
font_02_sfnt_off0001371c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1371C 16792 bytes