What’s Vulnerable › Vulnerabilities

CVE-2026-78383: Apache Tomcat: AJP DoS via missing request body

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-23 · updated 2026-09-23
• Weakness: CWE-770

Description

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 products

• 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; from 8.5.0 through 8.5.100; from 7.0.0 through 7.0.109

References

• https://lists.apache.org/thread/tyqcqk99g7ghgk22641vf67vghcyswnw
• http://www.openwall.com/lists/oss-security/2026/09/23/25

Get alerted when CVE-2026-78383 or the next vulnerability affects your stack