CVE-2026-77791

Cve • September 23, 2026

Uncontrolled Resource Consumption vulnerability in Apache Tomcat during sending of WebSocket close message enabled a DoS attack. This issue affects Apache Tomcat: from 11.0.0-M5 through 11.0.25, from 10.1.8 through 10.1.59, from 9.0.74 through 9.0.121. The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.88 through 8.5.100. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

CWE-400 : Uncontrolled Resource Consumption

Default Status: unaffected

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Multiple Vulnerabilities Discovered in Apache Tomcat Five critical vulnerabilities have been identified in Apache Tomcat, affecting versions from 8.5.0 to 11.0.25. These include CVE-2026-77762, a race condition allowing HTTP/2 request injection; CVE-2026-78383, enabling denial of service via unauthenticated AJP requests; CVE-2026-77791, which allows DoS attacks through uncontrolled resource consumption; CVE-2026-78437, related to incomplete cleanup causing request failures; and CVE-2026-86350, a regression causing HTTP request smuggling. Users are advised to upgrade to the latest versions (11.0.26, 10.1.60, or 9.0.122) to mitigate these vulnerabilities. The vulnerabilities impact both supported and end-of-life versions of Apache Tomcat, posing significant risks to web applications relying on this server software. 7 sources 61

Extracted Entities

CVE-2026-77791

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Extracted Entities

Attack Types (1)

CVEs (1)

CWE Weaknesses (1)

Platforms (1)