Description
An h2c direct connection to Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M5 to 9.0.36 and 8.5.1 to 8.5.56 did not release the HTTP/1.1 processor after the upgrade to HTTP/2. If a sufficient number of such requests were made, an OutOfMemoryException could occur leading to a denial of service.
Affected products
apache: tomcat; debian: debian linux; netapp: oncommand system manager; opensuse: leap; canonical: ubuntu linux; oracle: agile engineering data management; oracle: agile product lifecycle management; oracle: communications instant messaging server; oracle: fmw platform; oracle: instantis enterprisetrack; oracle: managed file transfer; oracle: mysql enterprise monitor; oracle: siebel ui framework; oracle: workload manager
References10
- lists.apache.org/thread.html/r61f411cf82488d6ec213063fc15feeeb8… Mailing ListRelease NotesVendor Advisory
- lists.apache.org/thread.html/r61f411cf82488d6ec213063fc15feeeb8… Mailing ListRelease NotesVendor Advisory
- www.oracle.com//security-alerts/cpujul2021.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpuApr2021.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpujan2021.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpujan2022.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpuoct2020.html PatchThird Party Advisory
- www.oracle.com//security-alerts/cpujul2021.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpuApr2021.html PatchThird Party Advisory
- www.oracle.com/security-alerts/cpujan2021.html PatchThird Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 64% percentile: 99 · as of 11 November 2026
- CWE
- CWE-401CWE-476
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