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Advisory details: gitlab / maven/org.apache.tomcat/tomcat-coyote/CVE-2025-53506
Advisory ID gitlab/maven/org.apache.tomcat/tomcat-coyote/CVE-2025-53506
Aliases CVE-2025-53506
GHSA-25xr-qj8w-c4vf
Summary Apache Tomcat Coyote vulnerable to Denial of Service via excessive HTTP/2 streams 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.
Status Published
Exploitability 0.5
Weighted Severity 0.0
Risk
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (3)
CWE-400 Uncontrolled Resource Consumption
CWE-937 OWASP Top Ten 2013 Category A9 - Using Components with Known Vulnerabilities
CWE-1035 OWASP Top Ten 2017 Category A9 - Using Components with Known Vulnerabilities
System Score Found at
cvssv3.1 https://gitlab.com/gitlab-org/advisories-community/-/blob/main/maven/org.apache.tomcat/tomcat-coyote/CVE-2025-53506.yml
Reference id Reference type URL
https://github.com/apache/tomcat
https://github.com/apache/tomcat/commit/2aa6261276ebe50b99276953591e3a2be7898bdb
https://github.com/apache/tomcat/commit/434772930f362145516dd60681134e7f0cf8115b
https://github.com/apache/tomcat/commit/be8f330f83ceddaf3baeed57522e571572b6b99b
https://lists.apache.org/thread/p09775q0rd185m6zz98krg0fp45j8kr0
https://lists.debian.org/debian-lts-announce/2025/07/msg00009.html
CVE-2025-53506 https://nvd.nist.gov/vuln/detail/CVE-2025-53506
GHSA-25xr-qj8w-c4vf https://github.com/advisories/GHSA-25xr-qj8w-c4vf
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Found at https://gitlab.com/gitlab-org/advisories-community/-/blob/main/maven/org.apache.tomcat/tomcat-coyote/CVE-2025-53506.yml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none

Vector: SSVCv2/E:N/A:Y/T:P/P:M/B:A/M:M/D:T/2025-07-11T13:46:01Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2025/53xxx/CVE-2025-53506.json

Source Advisory: vulnrichment/CVE-2025-53506

View SSVC decision tree 
[{'Exploitation': 'none'},
 {'Automatable': 'yes'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]