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CVE-2026-59903 (GCVE-0-2026-59903)

Vulnerability from cvelistv5 – Published: 2026-08-17 17:56 – Updated: 2026-08-17 18:14
VLAI
Title
Netty: Cache Poisoning and Information Disclosure via CORS Vary Header Overwrite
Summary
Netty is an asynchronous, event-driven network application framework. Prior to 4.1.137.Final and 4.2.17.Final, io.netty.handler.codec.http.cors.CorsHandler setVaryHeader replaces application Vary headers such as Authorization or Cookie with Origin, allowing a caching proxy or CDN to reuse authenticated responses across users and disclose sensitive information. This issue is fixed in versions 4.1.137.Final and 4.2.17.Final.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-17 18:13 UTC
CWE
  • CWE-524 - Use of Cache Containing Sensitive Information
Assigner
References
Impacted products
Vendor Product Version CPE status
netty netty Affected: < 4.1.137.Final
Affected: >= 4.2.0.Final, < 4.2.17.Final
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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