CVE-2025-53506 Details
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.

Users are recommended to upgrade to version 11.0.9, 10.1.43 or 9.0.107, which fix the issue.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2025-53506
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
0.15 Probability of exploitation activity being observed over the next 30 days (36th percentile)
CVSS score for CVE-2025-53506
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
7.5 High
Products affected by CVE-2025-53506
Tomcat 10.1.6
Tomcat 10.1.7
Tomcat 10.1.8
Tomcat 10.1.9
Tomcat 11.0.0
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Low
More on DVE scores

CVE-2025-53506 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 22,148 27.26%
CN 14,076 17.33%
IN 5,531 6.81%
DE 4,376 5.39%
BR 2,972 3.66%
KR 2,837 3.49%
JP 2,459 3.03%
SG 1,977 2.43%
FR 1,767 2.17%
GB 1,759 2.17%

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CVE-2025-53506 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Technology 49,710 79.29%
Telecommunications 8,267 13.19%
Education 1,606 2.56%
Government/Politics 635 1.01%
Business Services 524 0.84%
Finance 425 0.68%
Healthcare/Wellness 256 0.41%
Manufacturing 253 0.40%
Retail 189 0.30%
Transportation 131 0.21%

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