Malicious PDF — malware analysis report

Static analysis result for SHA-256 de7f2a60c052ff21…

MALICIOUS

PDF

80.7 KB Created: 2021-06-10 12:35:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 601e97983362d31e589568ca3a81b07c SHA-1: 3cc06b6f86ec33e2232c778ee434e11a2bf41f73 SHA-256: de7f2a60c052ff219359213b3e74dec99e625e2fd62a9ce982b7665ee32929de
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress upload directories. The document body contains obfuscated text and metadata suggesting it was generated by wkhtmltopdf, and the embedded URLs are likely used to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://huntic.ru/uplcv?utm_term=shiva+shiva+motu+patlu+shiva+shiva PDF link annotation
    • https://aihr-iadh.org/uploads/FCK_files/file/jonebanelebasagewut.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/nuvpnimnmib5ns69dqtek1a7lm/28258248310.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/04f8a0a4900c0fea12d9a9eaf94d23d9/sozudexatusoxumarezewovuf.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb51ee4e40---29295306269.pdfIn PDF document text
    • https://aduanaldelvalle.com/userfiles/file/gopetijoben.pdfIn PDF document text
    • http://doyen.cc/images/upload/File/liwososote.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/01c442aed65a0ae66207d1c1f57cc03d/sotipegeraregiwip.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad014e1b5e4---40216401154.pdfIn PDF document text
    • https://allcreaturesinc.com/files/files/lizisutuzamuwalaz.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/5380ecc1086197e753bdfba81ad3a147/jelatarebunirozapoxujijoj.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/29630747696.pdfIn PDF document text
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16207904608113.pdfIn PDF document text
    • https://wulf-sanitaer.de/wp-content/plugins/super-forms/uploads/php/files/uhii7g84iqnd7sqpi91dg57efa/sopiwifawupudovef.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b37207e9aa1---jifasugaralazifonaruf.pdfIn PDF document text
    • https://nothingbutsafetyglasses.com/userfiles/file/xojaxovuwebavux.pdfIn PDF document text
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/gu0r4kj2n83uhqpvc2btuc42ch/lefelexanefeb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e92d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE92D 5728 bytes
SHA-256: 43f8c9ce506233c24075ffe60f26b3e2b8582417a8ec7eeca0fc35b65b1263e6
font_01_sfnt_off0000fcf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCF6 5124 bytes
SHA-256: 9cfa748121e9a11009bb07489252af36b06de6c022e3b348e403e739a666b02f
font_02_sfnt_off00010e47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E47 11580 bytes
SHA-256: 9d2795a2d162185d653af940ab3114993be2406eda5721e294ec276956759baf