Tomcat8: Uncontrolled Resource Consumption vulnerability
Affects tomcat8Source GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in 11.0.9 : patch tomcat8 soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 2.1% chance of exploitation in 30 days – higher than 81% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 11.0.9
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 10 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10tomcat10pkg:deb/ubuntu/tomcat10?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTStomcat10pkg:deb/ubuntu/tomcat10?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTStomcat11pkg:deb/ubuntu/tomcat11?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 25.10tomcat10pkg:deb/ubuntu/tomcat10?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10tomcat11pkg:deb/ubuntu/tomcat11?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTStomcat10pkg:deb/ubuntu/tomcat10?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
Uncontrolled Resource Consumption vulnerability in Apache Tomcat if an HTTP/2 client did not acknowledge the initial settings frame that reduces the maximum permitted concurrent streams. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.8, from 10.1.0-M1 through 10.1.42, from 9.0.0.M1 through 9.0.106. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 through 8.5.100. Other EOL versions may also be affected. Users are recommended to upgrade to version 11.0.9, 10.1.43 or 9.0.107, which fix the issue.
References
- ubuntu.com/security/CVE-2025-53506 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-53506 (opens in a new tab)
- github.com/apache/tomcat/commit/be8f330f83ceddaf3baeed57522e571572b6b99b (opens in a new tab)
- github.com/apache/tomcat/commit/2aa6261276ebe50b99276953591e3a2be7898bdb (opens in a new tab)
- github.com/apache/tomcat/commit/434772930f362145516dd60681134e7f0cf8115b (opens in a new tab)
- lists.apache.org/thread/p09775q0rd185m6zz98krg0fp45j8kr0 (opens in a new tab)