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CVE-2026-78383: CWE-770 Allocation of resources without limits or throttling in Apache Software Foundation Apache Tomcat

0
High
VulnerabilityCVE-2026-78383cvecve-2026-78383cwe-770
Published: 09/23/2026 (09/23/2026, 11:23:15 UTC)
Source: CVE Database V5
Vendor/Project: Apache Software Foundation
Product: Apache Tomcat

Description

CVE-2026-78383 is a resource allocation vulnerability in Apache Tomcat affecting multiple versions from 7.0.0 through 11.0.25. It allows an unauthenticated AJP request to pin an AJP processing thread, resulting in denial of service. The issue is addressed in Apache Tomcat versions 11.0.26, 10.1.60, and 9.0.122.

Affected software

Apache Software Foundation

Apache Tomcat

Affected versions
>=11.0.0-M1 <=11.0.25>=10.1.0-M1 <=10.1.59>=9.0.0.M1 <=9.0.121>=8.5.0 <=8.5.100>=7.0.0 <=7.0.109
org.apache.tomcat/tomcat
pkg:maven/org.apache.tomcat/tomcat
Affected versions
>=11.0.0-M1 <=11.0.25>=10.1.0-M1 <=10.1.59>=9.0.0.M1 <=9.0.121>=8.5.0 <=8.5.100>=7.0.0 <=7.0.109

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/23/2026, 11:48:51 UTC

Technical Analysis

This vulnerability (CWE-770) in Apache Tomcat involves allocation of resources without limits or throttling in the AJP connector. An unauthenticated attacker can send a crafted AJP request that pins an AJP processing thread, causing denial of service by exhausting available threads. Affected versions include 11.0.0-M1 through 11.0.25, 10.1.0-M1 through 10.1.59, 9.0.0.M1 through 9.0.121, and older EOL versions 8.5.0 through 8.5.100 and 7.0.0 through 7.0.109. The issue is fixed in versions 11.0.26, 10.1.60, and 9.0.122.

Potential Impact

An unauthenticated attacker can cause denial of service by exhausting AJP processing threads, potentially disrupting service availability for legitimate users.

Mitigation Recommendations

Users should upgrade affected Apache Tomcat versions to 11.0.26, 10.1.60, or 9.0.122 where the vulnerability is fixed. No other mitigation or temporary workaround is indicated.

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Technical Details

Data Version
5.2
Assigner Short Name
apache
Date Reserved
2026-08-24T13:38:58.809Z
State
PUBLISHED

Threat ID: 6ab3b90df7a7c54106b30f14

Added to database: 09/23/2026, 11:33:33 UTC

Last enriched: 09/23/2026, 11:48:51 UTC

Last updated: 09/23/2026, 13:54:21 UTC

Views: 4

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