High severity7.5NVD Advisory· Published Sep 23, 2026· Updated Sep 23, 2026
CVE-2026-78383
CVE-2026-78383
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.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected products
10- osv-coords9 versionspkg:bitnami/tomcatpkg:rpm/opensuse/tomcat10&distro=openSUSE%20Tumbleweedpkg:rpm/opensuse/tomcat11&distro=openSUSE%20Tumbleweedpkg:rpm/opensuse/libtcnative-1-0&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/libtcnative-2-0&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/tomcat&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/tomcat10&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/tomcat11&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/tomcat&distro=openSUSE%20Tumbleweed
>= 7.0.0, < 9.0.45+ 8 more
- (no CPE)range: >= 7.0.0, < 9.0.45
- (no CPE)range: < 10.1.60-1.1
- (no CPE)range: < 11.0.26-1.1
- (no CPE)range: < 1.3.9-160000.1.1
- (no CPE)range: < 2.0.16-160000.1.1
- (no CPE)range: < 9.0.122-160000.1.1
- (no CPE)range: < 10.1.60-160000.1.1
- (no CPE)range: < 11.0.26-160000.1.1
- (no CPE)range: < 9.0.122-1.1
Patches
Vulnerability mechanics
References
2News mentions
4- ⚡ Weekly Recap: NetScaler and FortiMail 0-Days, AI Coding Leaks, Spectre v2 and Ransomware ArrestsThe Hacker News · Oct 5, 2026
- Apache: 25 Vulnerabilities Disclosed, Critical Flaws Hit Tomcat on Sep 23-24, 2026Vypr Intelligence · Sep 24, 2026
- Apache Tomcat Update Fixes WebSocket and HTTP/2 Flaws Affecting Server SecurityCyber Security News · Sep 24, 2026
- Apache Tomcat: 12 Vulnerabilities Including HTTP/2 Smuggling and Auth Bypass Disclosed TogetherVypr Intelligence · Sep 23, 2026