CVE-2026-59083 Details
Improper Handling of URL Encoding (Hex Encoding) vulnerability in Apache Tomcat's rewrite valve allowed security constraint bypass for some configurations.

This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.23, from 10.1.0-M1 through 10.1.56, from 9.0.0.M1 through 9.0.119, from 8.5.0 through 8.5.100. Other versions that have reached end of support may also be affected.

Users are recommended to upgrade to version 11.0.24, 10.1.57 or 9.0.120, which fix the issue.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2026-59083
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%).
0.38 Probability of exploitation activity being observed over the next 30 days (30th percentile)
CVSS score for CVE-2026-59083
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.
9.1 Critical
Products affected by CVE-2026-59083
Tomcat 7.0.47
Tomcat 7.0.5
Tomcat 7.0.50
Tomcat 7.0.52
Tomcat 7.0.53
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
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CVE-2026-59083 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 5,936 26.42%
CN 4,913 21.86%
DE 1,108 4.93%
KR 1,100 4.89%
IN 998 4.44%
BR 682 3.03%
SG 647 2.88%
JP 518 2.31%
FR 437 1.94%
HK 412 1.83%

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CVE-2026-59083 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 13,038 77.64%
Telecommunications 2,418 14.40%
Education 427 2.54%
Government/Politics 229 1.36%
Finance 136 0.81%
Business Services 133 0.79%
Manufacturing 91 0.54%
Retail 47 0.28%
Media/Entertainment 45 0.27%
Healthcare/Wellness 45 0.27%

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