CVE-2025-53506
mediumpriority · track · 1EPSS 0.021 · 82 %ileDEEURUUSEPSS · scored 2026-10-27
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.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixedtomcat-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-admin-webapps-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-admin-webapps-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-docs-webapp-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-docs-webapp-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-el-3_0-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-el-3_0-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-javadoc-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-javadoc-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-jsp-2_3-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-jsp-2_3-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-lib-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-lib-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-servlet-4_0-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-servlet-4_0-api-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-webapps-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server 12 SP5-LTSSsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedtomcat-webapps-0:9.0.115-3.160.1.noarch as component of SUSE Linux Enterprise Server LTSS Extended Security 12 SP5suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.3–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (94)
Products and version ranges known to be affected.
advisories (6)
Vendor and ecosystem advisories describing this.
- SUSE-SU-2026:1058-1Security update for tomcat2026-03-26csaf · suse_csafDE
Security update for tomcat
- WID-SEC-W-2025-1468Apache Tomcat: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2025-07-07csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Apache Tomcat ausnutzen, um einen Denial of Service Angriff durchzuführen.
- WID-SEC-W-2025-1905IBM QRadar SIEM Komponente: Mehrere SchwachstellenDeutsch2025-08-25csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM Komponenten ausnutzen, um Daten zu manipulieren, um einen Denial of Service Angriff durchzuführen, um beliebigen Programmcode auszuführen, um Sicherheitsvorkehrungen zu umgehen, und um Informationen offenzulegen.
- WID-SEC-W-2026-2189Dell PowerProtect Data Domain: Mehrere SchwachstellenDeutsch2026-07-02csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Dell PowerProtect Data Domain ausnutzen, um seine Privilegien zu erhöhen um beliebigen Programmcode auszuführen, um Sicherheitsvorkehrungen zu umgehen, um einen Denial of Service Angriff durchzuführen, um einen Cross-Site Scripting Angriff durchzuführen, um Informationen offenzulegen, und um Dateien zu manipulieren.
- GHSA-25xr-qj8w-c4vfApache Tomcat Coyote vulnerable to Denial of Service via excessive HTTP/2 streams2025-07-10ghsa · osvUS
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. Users are recommended to upgrade to version 11.0.9, 10.1.43 or 9.0.107, which fix the issue.
- BIT-tomcat-2025-53506Apache Tomcat: DoS via excessive h2 streams at connection start2025-07-16vendor · osvUS
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 through 11.0.8, from 10.1.0 through 10.1.42, from 9.0.0 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.
also known as (6)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (9)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2025-53506cnnvd
- https://lists.apache.org/thread/p09775q0rd185m6zz98krg0fp45j8kr0cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2025-53506cnnvd
- https://tomcat.apache.org/Patchcnnvd
- https://vigilance.fr/vulnerability/Apache-Tomcat-denial-of-service-via-Excessive-HTTP-2-Streams-47628cnnvd
- https://lists.apache.org/thread/p09775q0rd185m6zz98krg0fp45j8kr0enisa_euvd
- http://www.openwall.com/lists/oss-security/2025/07/10/13nvd
- https://lists.apache.org/thread/p09775q0rd185m6zz98krg0fp45j8kr0Issue TrackingMailing ListVendor Advisorynvd
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