Evidence used
- No CISA KEV confirmation is currently recorded.
- The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
- EPSS is 4.60% for the current model date.
BlackTreeCVE IntelligenceApache Software Foundation · Apache Tomcat
High technical severity; prioritise exposed affected systems while verifying vendor guidance.
Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.
A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.
| Distribution release | Source package | Vendor state | Fixed version | Evidence |
|---|---|---|---|---|
| Debian trixietrixie · source | tomcat10 | Vendor fix publishedDebian records a fixed source-package version for this release. | 10.1.25-1 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Debian trixietrixie · source | tomcat9 | Vendor fix publishedDebian records a fixed source-package version for this release. | 9.0.70-2 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Debian bookwormbookworm · source | tomcat10 | Vendor fix publishedDebian records a fixed source-package version for this release. | 10.1.34-0+deb12u1 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Debian bookwormbookworm · source | tomcat9 | Vendor fix publishedDebian records a fixed source-package version for this release. | 9.0.70-2 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Debian forkyforky · source | tomcat10 | Vendor fix publishedDebian records a fixed source-package version for this release. | 10.1.25-1 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Debian forkyforky · source | tomcat9 | Vendor fix publishedDebian records a fixed source-package version for this release. | 9.0.70-2 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Debian sidsid · source | tomcat10 | Vendor fix publishedDebian records a fixed source-package version for this release. | 10.1.25-1 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Debian sidsid · source | tomcat9 | Vendor fix publishedDebian records a fixed source-package version for this release. | 9.0.70-2 | Debian Security Tracker ↗Source updated 6 Oct 2026 |
| Ubuntu 24.04 LTSnoble · esm-apps | tomcat10 | Vendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree. | 10.1.16-1ubuntu0.1~esm2 | Canonical Ubuntu Security ↗Source updated 5 Oct 2026 |
| Ubuntu 24.04 LTSnoble · esm-apps | tomcat9 | Vendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree. | 9.0.70-2ubuntu0.1+esm2 | Canonical Ubuntu Security ↗Source updated 5 Oct 2026 |
These OSV and GitHub advisory ranges apply only to the named package and ecosystem. A listed fixed version is not a universal product patch or proof that an update is installed.
| Ecosystem and package | Affected range | First fixed version | Evidence |
|---|---|---|---|
| Mavenorg.apache.tomcat.embed:tomcat-embed-core | ECOSYSTEM: introduced 11.0.0-M1; fixed 11.0.0-M21 | 11.0.0-M21 | OSV record ↗aggregator derived · 10 Sep 2026 |
| Mavenorg.apache.tomcat.embed:tomcat-embed-core | ECOSYSTEM: introduced 10.1.0-M1; fixed 10.1.25 | 10.1.25 | OSV record ↗aggregator derived · 10 Sep 2026 |
| Mavenorg.apache.tomcat.embed:tomcat-embed-core | ECOSYSTEM: introduced 9.0.0-M1; fixed 9.0.90 | 9.0.90 | OSV record ↗aggregator derived · 10 Sep 2026 |
| Mavenorg.apache.tomcat.embed:tomcat-embed-core | ECOSYSTEM: introduced 8.5.0; last affected 8.5.100 | Not stated | OSV record ↗aggregator derived · 10 Sep 2026 |
| Mavenorg.apache.tomcat:tomcat-coyote | ECOSYSTEM: introduced 11.0.0-M1; fixed 11.0.0-M21 | 11.0.0-M21 | OSV record ↗aggregator derived · 10 Sep 2026 |
| Mavenorg.apache.tomcat:tomcat-coyote | ECOSYSTEM: introduced 10.1.0-M1; fixed 10.1.25 | 10.1.25 | OSV record ↗aggregator derived · 10 Sep 2026 |
| Mavenorg.apache.tomcat:tomcat-coyote | ECOSYSTEM: introduced 9.0.0-M1; fixed 9.0.90 | 9.0.90 | OSV record ↗aggregator derived · 10 Sep 2026 |
| Mavenorg.apache.tomcat:tomcat-coyote | ECOSYSTEM: introduced 8.5.0; last affected 8.5.100 | Not stated | OSV record ↗aggregator derived · 10 Sep 2026 |
| mavenorg.apache.tomcat.embed:tomcat-embed-core | >= 11.0.0-M1, < 11.0.0-M21 | 11.0.0-M21 | GitHub advisory ↗github reviewed aggregator · 3 Nov 2025 |
| mavenorg.apache.tomcat.embed:tomcat-embed-core | >= 10.1.0-M1, < 10.1.25 | 10.1.25 | GitHub advisory ↗github reviewed aggregator · 3 Nov 2025 |
| mavenorg.apache.tomcat.embed:tomcat-embed-core | >= 9.0.0-M1, < 9.0.90 | 9.0.90 | GitHub advisory ↗github reviewed aggregator · 3 Nov 2025 |
| mavenorg.apache.tomcat.embed:tomcat-embed-core | >= 8.5.0, <= 8.5.100 | Not stated | GitHub advisory ↗github reviewed aggregator · 3 Nov 2025 |
| mavenorg.apache.tomcat:tomcat-coyote | >= 11.0.0-M1, < 11.0.0-M21 | 11.0.0-M21 | GitHub advisory ↗github reviewed aggregator · 3 Nov 2025 |
| mavenorg.apache.tomcat:tomcat-coyote | >= 10.1.0-M1, < 10.1.25 | 10.1.25 | GitHub advisory ↗github reviewed aggregator · 3 Nov 2025 |
| mavenorg.apache.tomcat:tomcat-coyote | >= 9.0.0-M1, < 9.0.90 | 9.0.90 | GitHub advisory ↗github reviewed aggregator · 3 Nov 2025 |
| mavenorg.apache.tomcat:tomcat-coyote | >= 8.5.0, <= 8.5.100 | Not stated | GitHub advisory ↗github reviewed aggregator · 3 Nov 2025 |
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
The vendor explicitly identifies these products as affected by this CVE.
High technical severity; prioritise exposed affected systems while verifying vendor guidance.
Patch availableImproper Handling of Exceptional Conditions, Uncontrolled Resource Consumption vulnerability in Apache Tomcat. When processing an HTTP/2 stream, Tomcat did not handle some cases of excessive HTTP headers correctly. This led to a miscounting of active HTTP/2 streams which in turn led to the use of an incorrect infinite timeout which allowed connections to remain open which should have been closed. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.0-M20, from 10.1.0-M1 through 10.1.24, from 9.0.0-M1 through 9.0.89. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 though 8.5.100. Other EOL versions may also be affected. Users are recommended to upgrade to version 11.0.0-M21, 10.1.25 or 9.0.90, which fixes the issue.
Improper Handling of Exceptional Conditions, Uncontrolled Resource Consumption vulnerability in Apache Tomcat. When processing an HTTP/2 stream, Tomcat did not handle some cases of excessive HTTP headers correctly. This led to a miscounting of active HTTP/2 streams which in turn led to the use of an incorrect infinite timeout which allowed connections to remain open which should have been closed. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.0-M20, from 10.1.0-M1 through 10.1.24, from 9.0.0-M1 through 9.0.89. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 though 8.5.100. Other EOL versions may also be affected. Users are recommended to upgrade to version 11.0.0-M21, 10.1.25 or 9.0.90, which fixes the issue.
The product does not handle or incorrectly handles an exceptional condition.
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
Improper Handling of Exceptional Conditions, Uncontrolled Resource Consumption vulnerability in Apache Tomcat. When processing an HTTP/2 stream, Tomcat did not handle some cases of excessive HTTP headers correctly. This led to a miscounting of active HTTP/2 streams which in turn led to the use of an incorrect infinite timeout which allowed connections to remain open which should have been closed. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.0-M20, from 10.1.0-M1 through 10.1.24, from 9.0.0-M1 through 9.0.89. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 though 8.5.100. Other EOL versions may also be affected. Users are recommended to upgrade to version 11.0.0-M21, 10.1.25 or 9.0.90, which fixes the issue.
The product does not handle or incorrectly handles an exceptional condition.
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
CWE-755: Improper Handling of Exceptional Conditions. The product does not handle or incorrectly handles an exceptional condition.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
Operational remediation based on structured source evidence.
Published 3 Jul 2024 · Last source change 3 Nov 2025, 19:29 UTC · CWE-755 · Improper Handling of Exceptional Conditions
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