Advisory severityHigh7.5Apache Software Foundation

High [CVE-2026-78383] Allocation of resources without limits or throttling vulnerability in Apache Tomcat allows an unauthenticated AJP request to pin an AJP processing thread leading to denial of service

This high-severity Apache Software Foundation advisory covers CVE-2026-78383 affecting Apache Tomcat.

Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.

CVE-2026-78383 Source published Sep 23, 2026Source updated Sep 23, 2026

VulniPulse record published Sep 23, 2026Record updated Sep 23, 2026

CVE-2026-78383

Affected products & platforms

Apache Software FoundationTomcat

Open source advisory

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Summary

Allocation of resources without limits or throttling vulnerability in Apache Tomcat allows an unauthenticated AJP request to pin an AJP processing thread leading to denial of service.

This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121.

The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. 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.

Affected versions

11.0.0-M1 through 11.0.25
10.1.0-M1 through 10.1.59
9.0.0.M1 through 9.0.121.
8.5.0 through 8.5.100
7.0.0 through 7.0.109.
through 9.0.121
through 7.0.109

Official advisory · high-confidence parse· fetched 13 days ago·verify at source

Fixed versions

11.0.26
10.1.60
9.0.122

Official advisory · high-confidence parse· fetched 13 days ago·verify at source

Mitigation checklist

Recommended fix / mitigation

Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

Official advisory · high-confidence parse· fetched 13 days ago·verify at source

Sources

Official and corroborating records used to build this advisory.

Official vendor advisoryofficial
Official advisory page fetched and parsed; accepted detail fields are attributed to this page.
Apache Software Foundation
CVE.org CNA recordCVE.org
Independent CNA record used for near-real-time discovery and missed-CVE reconciliation. Discovered from the machine-readable feed https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/delta.json; this link opens the CVE.org record for CVE-2026-78383 instead of the raw feed document.
CVE Program

Cross-references

Validate CVE metadata against the authoritative registries.

CVE-2026-78383NVD CVE.org MITRE

Official resources

Apache Tomcat security bulletins (per major version) (target: 11.0.26 / 10.1.60 / 9.0.122)
Official documentation
This advisory names 11.0.26 / 10.1.60 / 9.0.122 as the first fixed releases — official upgrade documentation for Apache Tomcat security bulletins (per major version).
ASF Security — reporting & CVE process
Official documentation
The Apache Software Foundation's official security page: how ASF CVEs are published and where each project's advisories live.
Apache project downloads (fixed releases)
Official documentation
Official ASF download tree — fetch the fixed release named in this advisory from the project's directory.

Discussion(0)

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