Resource exhaustion in Apache Tomcat - CVE-2026-78437
Published: September 23, 2026
Vulnerability identifier: #VU151842
CSH Severity: Low
CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-78437
CWE-ID: CWE-400
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause another user's request to fail.
The vulnerability exists due to improper handling of malformed HTTP/2 requests in HTTP/2 request processing when handling a malformed HTTP/2 request. A remote attacker can send a malformed HTTP/2 request to cause another user's request to fail.
Successful exploitation depends on timing.
Affected software
Apache Tomcat
How to mitigate CVE-2026-78437
Install security update from vendor's website.
Apache Tomcat - addressed in versions 9.0.122, 10.1.60, 11.0.26