CVE-2026-66422 Details
Improper Authorization vulnerability in Apache Tomcat cause by security-role-ref definitions being incorrectly used as role aliases within the Realm in additional to the correct usage with Request.isUserInRole().



This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.24, from 10.1.0-M1 through 10.1.57, from 9.0.25 through 9.0.120.



The following versions were EOL at the time the CVE was created but are
known to be affected: from 8.5.46 through 8.5.100, from 7.0.97 through 7.0.109. Other unsupported versions may also be affected.



Users are recommended to upgrade to version 11.0.25, 10.1.58 or 9.0.121, which fix the issue.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2026-66422
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%).
0.57 Probability of exploitation activity being observed over the next 30 days (45th percentile)
CVSS score for CVE-2026-66422
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.
8.1 High
Products affected by CVE-2026-66422
Tomcat 9.0.74
Tomcat 9.0.75
Tomcat 9.0.76
Tomcat 9.0.78
Tomcat 9.0.79
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-2026-66422 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 3,427 26.47%
CN 2,839 21.93%
IN 737 5.69%
DE 680 5.25%
KR 513 3.96%
BR 372 2.87%
SG 358 2.76%
JP 331 2.56%
GB 295 2.28%
FR 277 2.14%

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CVE-2026-66422 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 7,818 78.20%
Telecommunications 1,335 13.35%
Education 295 2.95%
Government/Politics 142 1.42%
Finance 77 0.77%
Business Services 73 0.73%
Manufacturing 59 0.59%
Retail 41 0.41%
Healthcare/Wellness 38 0.38%
Transportation 22 0.22%

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