CVE-2026-66299

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Source
https://cve.org/CVERecord?id=CVE-2026-66299
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-66299.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-66299
Downstream
Published
2026-07-28T14:29:05.810Z
Modified
2026-08-12T03:51:36.643117295Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
Apache Tomcat: DoS via WebSocket chat example
Details

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.

Database specific 
{
    "cwe_ids": [
        "CWE-400"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/66xxx/CVE-2026-66299.json",
    "cna_assigner": "apache",
    "unresolved_ranges": [
        {
            "extracted_events": [
                {
                    "introduced": "11.0.0-M20"
                },
                {
                    "last_affected": "11.0.24"
                },
                {
                    "introduced": "10.1.24"
                },
                {
                    "last_affected": "10.1.57"
                },
                {
                    "introduced": "9.0.89"
                },
                {
                    "last_affected": "9.0.120"
                }
            ],
            "source": "AFFECTED_FIELD"
        },
        {
            "extracted_events": [
                {
                    "introduced": "11.0.0-M20"
                },
                {
                    "fixed": "11.0.24"
                },
                {
                    "introduced": "10.1.24"
                },
                {
                    "fixed": "10.1.57"
                },
                {
                    "introduced": "9.0.89"
                },
                {
                    "fixed": "9.0.120"
                }
            ],
            "source": "DESCRIPTION"
        }
    ]
}
References

Affected packages

Git / github.com/apache/tomcat

Affected ranges

Type
GIT
Repo
https://github.com/apache/tomcat
Events
Introduced
c400bf727cbc10198d3f52c29849d18660050b0c
Last affected
e9935d107776339a4a48cf4e32195a763fbf8379
Database specific
Show details 
{
    "cpe": [
        "cpe:2.3:a:apache:tomcat:11.0.0:milestone20:*:*:*:*:*:*",
        "cpe:2.3:a:apache:tomcat:11.0.0:milestone21:*:*:*:*:*:*",
        "cpe:2.3:a:apache:tomcat:11.0.0:milestone22:*:*:*:*:*:*",
        "cpe:2.3:a:apache:tomcat:11.0.0:milestone23:*:*:*:*:*:*",
        "cpe:2.3:a:apache:tomcat:11.0.0:milestone24:*:*:*:*:*:*",
        "cpe:2.3:a:apache:tomcat:11.0.0:milestone25:*:*:*:*:*:*",
        "cpe:2.3:a:apache:tomcat:11.0.0:milestone26:*:*:*:*:*:*"
    ],
    "source": "CPE_STRING",
    "extracted_events": [
        {
            "introduced": "11.0.0-milestone20"
        },
        {
            "last_affected": "11.0.0-milestone20"
        },
        {
            "introduced": "11.0.0-milestone21"
        },
        {
            "last_affected": "11.0.0-milestone21"
        },
        {
            "introduced": "11.0.0-milestone22"
        },
        {
            "last_affected": "11.0.0-milestone22"
        },
        {
            "introduced": "11.0.0-milestone23"
        },
        {
            "last_affected": "11.0.0-milestone23"
        },
        {
            "introduced": "11.0.0-milestone24"
        },
        {
            "last_affected": "11.0.0-milestone24"
        },
        {
            "introduced": "11.0.0-milestone25"
        },
        {
            "last_affected": "11.0.0-milestone25"
        },
        {
            "introduced": "11.0.0-milestone26"
        },
        {
            "last_affected": "11.0.0-milestone26"
        }
    ]
}

Affected versions

11.*
11.0.0-milestone20
11.0.0-milestone21
11.0.0-milestone22
11.0.0-milestone23
11.0.0-milestone24
11.0.0-milestone25
11.0.0-milestone26

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-66299.json"