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Apache disclosed CVE-2026-42498, a low-severity information-disclosure flaw in Tomcat’s WebSocket client. After authenticating a WebSocket request, the client can send its most recent HTTP authentication header to an unexpected redirect-target host, potentially exposing credentials or other sensitive header contents. The vulnerability is classified as CWE-200, Exposure of Sensitive Information to an Unauthorized Actor.
Affected releases include Tomcat 11.0.0-M1 through 11.0.21, 10.1.0-M1 through 10.1.54, and 9.0.2 through 9.0.117; MITRE also identifies affected version lines including 7.0 and 8.5, which may be unsupported. Organizations should upgrade to Tomcat 11.0.22 or later, 10.1.55 or later, or 9.0.118 or later, and assess WebSocket clients that authenticate before following redirects to external hosts.
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Apache disclosed a low-severity CWE-200 vulnerability in which Tomcat's WebSocket client can send a recent HTTP authentication header to an unexpected redirect target after authentication. The issue, identified by lokerxx, affects specified Tomcat 7.0, 8.5, 9.0, 10.1, and 11.0 releases; Apache advised upgrading to 11.0.22, 10.1.55, or 9.0.118, as applicable.
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Apache disclosed **CVE-2026-59083**, a vulnerability in Tomcat's `RewriteValve` caused by incorrect URL decoding of hex-encoded characters that can let attackers bypass security controls in some configurations. The issue is classified as **CWE-177** and was described as low severity by Apache, though the CVE record notes network attackability with low attack complexity, no privileges required, and no user interaction. Apache said the flaw affects supported Tomcat branches **11.0.0-M1 through 11.0.23**, **10.1.0-M1 through 10.1.56**, and **9.0.0.M1 through 9.0.119**, with reports also listing **8.5.0 through 8.5.100** as affected. Apache and downstream advisories urged users to upgrade to fixed releases **11.0.24**, **10.1.57**, or **9.0.120**, while warning that older unsupported versions may also be vulnerable; versions before **8.0.0** were noted as unaffected in the oss-security disclosure. The vulnerability was published through Apache security pages, the Apache mailing list, and `oss-security`, with the CVE entry updated to include affected-version details, a CVSS v3.1 vector, and a CISA SSVC assessment.
Aug 28, 2026
Apache disclosed **CVE-2026-43515**, an improper-authorization flaw in Tomcat’s handling of security constraints. When multiple constraints specify an HTTP method for the same extension pattern, Tomcat may enforce only the first constraint, potentially allowing intended access restrictions to be applied incorrectly. The issue affects Tomcat 9.0.0.M1–9.0.117, 10.1.0-M1–10.1.54, and 11.0.0-M1–11.0.21; MITRE also lists legacy Tomcat 7.0.0–7.0.109 and 8.5.0–8.5.100 as affected. Apache also fixed **CVE-2026-41293**, a low-severity HTTP/2 request-header validation issue that can cause unexpected behavior in applications relying on Servlet API header values being specification-compliant. Organizations should upgrade to Tomcat **9.0.118**, **10.1.55**, or **11.0.22** or later; unsupported releases should be retired or moved to a supported fixed version. Apache had separately disclosed **CVE-2026-32990**, identifying an incomplete prior fix for CVE-2025-66614.
Aug 28, 2026
Apache Tomcat disclosed **CVE-2015-5345**, a low-severity information-disclosure flaw that lets unauthenticated users determine whether protected directories or web-application roots exist. Tomcat processed redirects for directory URLs missing a trailing slash before applying security constraints, exposing the presence of resources that should not be discoverable. Apache corrected the request-processing order by moving redirect handling into `DefaultServlet`, ensuring security constraints and enforcement filters are evaluated before redirects occur. Organizations should upgrade to Tomcat 6.0.45, 7.0.67, 8.0.30, 9.0.0.M3, or later.
Aug 29, 2026