← Vulnerability feed

Vulnerability record · CVE-2026-66299 · published 28 July 2026

CVE-2026-66299: Apache tomcat uncontrolled resource consumption vulnerability

Apache · Tomcat

Uncontrolled Resource Consumption vulnerability in Apache Tomcat's WebSocket chat example. This issue affects Apache Tomcat: from 11.0.0-M20 through 11.0.24, from 10.1.24 through 10.1.57, from 9.0.89 through 9.0.120. Users who have followed the security guidance to remove the examples web application are not affected by this issue. Users are recommended to remove the examples web application or to upgrade to version 11.0.25, 10.1.58 or 9.0.121 (when released), which fix the issue.

5.3 CVSS 3.1 Medium EPSS 0.74% · top 47.2% CWE-400 · Uncontrolled resource consumption
5.3CVSS 3.1 base score
0.74%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
27 Aug 2026Last modified by NVD

Description

Uncontrolled Resource Consumption vulnerability in Apache Tomcat's WebSocket chat example. This issue affects Apache Tomcat: from 11.0.0-M20 through 11.0.24, from 10.1.24 through 10.1.57, from 9.0.89 through 9.0.120. Users who have followed the security guidance to remove the examples web application are not affected by this issue. Users are recommended to remove the examples web application or to upgrade to version 11.0.25, 10.1.58 or 9.0.121 (when released), which fix the issue.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://lists.apache.org/thread/8owczcc1o8qw1rxmg9gvfk4w2jnh4l5k Mailing ListVendor Advisory
http://www.openwall.com/lists/oss-security/2026/07/28/25 Mailing ListThird Party Advisory

Track CVE-2026-66299 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2025-24813Apache Tomcat Default Servlet path equivalence enables RCE and file disclosureApache Tomcat mishandles path equivalence for names containing an internal dot, letting a remote unauthenticated attacker write files through the Def…KEVEPSS 100%analysed9.8CVE-2020-1938Apache Tomcat AJP connector file read and JSP execution flawApache Tomcat shipped an AJP Connector enabled by default that listened on all configured IP addresses, and Tomcat treats AJP connections as more tru…KEVEPSS 99%analysed9.8CVE-2016-8735Apache Tomcat JmxRemoteLifecycleListener remote code executionApache Tomcat's JmxRemoteLifecycleListener was not updated to match the Oracle CVE-2016-3427 credential-type fix, leaving a deserialization weakness …KEVEPSS 90%analysed8.1CVE-2017-12617Apache Tomcat Default Servlet JSP upload leads to remote code executionApache Tomcat with HTTP PUT enabled (for example, the Default servlet readonly parameter set to false) allows an attacker to upload a JSP file throug…KEVEPSS 100%analysed8.1CVE-2017-12615Apache Tomcat on Windows unrestricted JSP upload via HTTP PUTApache Tomcat 7.0.0 through 7.0.79 on Windows with HTTP PUT enabled (for example, Default servlet readonly set to false) allows an attacker to upload…KEVEPSS 100%analysed7.5CVE-2026-34486Apache Tomcat EncryptInterceptor bypass exposes sensitive dataApache Tomcat contains a missing encryption of sensitive data flaw: the fix for CVE-2026-29146 can be bypassed, allowing the EncryptInterceptor to be…KEVEPSS 6.6%analysed7.5CVE-2023-44487HTTP/2 Rapid Reset stream cancellation denial of serviceThe HTTP/2 protocol permits a client to cancel many streams quickly, and the server's handling of those resets consumes disproportionate resources. T…KEVEPSS 100%analysed9.8CVE-2026-65637Apache tomcat improper input validation vulnerabilityImproper Input Validation vulnerability in Apache Tomcat due to incomplete fix for CVE-2026-32990. This issue affects Apache Tomcat: from 11.0.20 thr…EPSS 0.74%

Source: NIST National Vulnerability Database (record CVE-2026-66299), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.