Malicious PDF — malware analysis report

Static analysis result for SHA-256 7caec166d0fa4d04…

MALICIOUS

PDF

74.8 KB Created: 2021-08-28 09:44:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 928b626d17c7fcb2d523fff3aff85eca SHA-1: ef25131f9cf9a865516867b24aa6dab88697f99b SHA-256: 7caec166d0fa4d045b25594716541d44b6f485bcbb459e52251e4cc4a55b63cd
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file contains a link farm pointing to multiple compromised WordPress sites and disposable hosting domains, suggesting an attempt to redirect users to malicious content. No scripts were extracted, and the document body was unreadable, but the presence of numerous external URIs and the heuristic firings strongly suggest a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160b0d86767f6a---45468585677.pdf In PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/qnca4a5ptqiho3sj6mr6899tgj/vinozafebupogatapafa.pdfIn PDF document text
    • http://donaldnathanlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/6665414017.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/89727790931.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf64614c5b5---sikisowe.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021082804202443.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/540501f02c154140b66a6d2b5bc7c00b/71896915719.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/b1phdggikpgpii0idar19ug8s6/xilinenudixigixol.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/telafubasirilefotuf.pdfIn PDF document text
    • http://bertoniamministrazione.it/bertoni/public/file/20528826046.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/xojenagubupizatuzex.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a25ee5e10d7---38887652816.pdfIn PDF document text
    • http://graphicyazd.com/ckfinder/userfiles/files/35575358358.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c842e69b41---98926350525.pdfIn PDF document text
    • https://kraftyz.in/ckfinder/userfiles/files/95155955380.pdfIn PDF document text
    • http://beateromer.com/bilder/file/lubixugaxusofidab.pdfIn PDF document text
    • https://jnvhardoi.org/ckfinder/userfiles/files/92712190358.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a661ce3cc79---zelusosojiberoletabigogu.pdfIn PDF document text
    • http://trlgpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vesazuxitutavokem.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/956db7635529c8ace58b1808aeee5698/37832985049.pdfIn PDF document text
    • http://akgikorea.com/file_upload/fck_upfile/file/28847005450.pdfIn PDF document text
    • http://mmckno2010.zkosuchdol.info/files/65307172394.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/jnmq0ac46njmpf8qpfhs9gc38m/jufuxogufekesera.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=sanitary+expenses+in+accountingPDF 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_off0000c01d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC01D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d82f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD82F 16620 bytes
SHA-256: ddf6fd7fef0d6cfb19a8e5af57e9b89dbd866bcd07e19bfea715e43e33994973
font_02_sfnt_off0001033f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1033F 10892 bytes
SHA-256: c5aaa0056ee47507c58c413fe82d5744f70870e5ab1d81ca1da59ec2cf48b817