What is CVE-2026-2742?

CVE-2026-2742 is a medium-severity security vulnerability in com.vaadin:flow-server (maven), affecting versions < 14.14.1. It is fixed in 14.14.1, 23.6.7, 24.9.8, 25.0.2.

Which packages are affected by CVE-2026-2742?

com.vaadin:flow-server (maven) versions = 25.0.0, < 25.0.2.

Is there a fix for CVE-2026-2742?

Yes. CVE-2026-2742 is fixed in 14.14.1, 23.6.7, 24.9.8, 25.0.2. Upgrade to this version or later.

Is CVE-2026-2742 exploitable, and should I be worried?

Whether CVE-2026-2742 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether CVE-2026-2742 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

CVE-2026-2742 in com.vaadin:flow-server

Q: Which packages are affected by CVE-2026-2742?

com.vaadin:flow-server (maven) versions = 25.0.0, < 25.0.2.

Q: Is there a fix for CVE-2026-2742?

Yes. CVE-2026-2742 is fixed in 14.14.1, 23.6.7, 24.9.8, 25.0.2. Upgrade to this version or later.

Q: Is CVE-2026-2742 exploitable, and should I be worried?

Whether CVE-2026-2742 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether CVE-2026-2742 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix CVE-2026-2742?

Upgrade: com.vaadin:flow-server to 14.14.1 or later, com.vaadin:flow-server to 23.6.7 or later, com.vaadin:flow-server to 24.9.8 or later, com.vaadin:flow-server to 25.0.2 or later, com.vaadin:vaadin to 25.0.2 or later, com.vaadin:vaadin to 24.9.8 or later, com.vaadin:vaadin to 23.6.7 or later, com.vaadin:vaadin to 14.14.1 or later.

Summary

Vaadin Vulnerable to Authentication Bypass When Accessing the /VAADIN Endpoint Without a Trailing Slash

An authentication bypass vulnerability exists in Vaadin 14.0.0 through 14.14.0, 23.0.0 through 23.6.6, 24.0.0 through 24.9.7 and 25.0.0 through 25.0.1, applications using Spring Security due to inconsistent path pattern matching of reserved framework paths.

Accessing the /VAADIN endpoint without a trailing slash bypasses security filters, and allowing unauthenticated users to trigger framework initialization and create sessions without proper authorization.

Users of affected versions using Spring Security should upgrade as follows: 14.0.0-14.14.0 upgrade to 14.14.1, 23.0.0-23.6.6 to 23.6.7, 24.0.0 - 24.9.7 to 24.9.8, and 25.0.0-25.0.1 upgrade to 25.0.2 or newer.

Please note that Vaadin versions 10-13 and 15-22 are no longer supported and users should update either to the latest 14, 23, 24, 25 version.

Impact

Affected versions

com.vaadin:flow-server (< 14.14.1) com.vaadin:flow-server (>= 23.0.0, < 23.6.7) com.vaadin:flow-server (>= 24.0.0, < 24.9.8) com.vaadin:flow-server (>= 25.0.0, < 25.0.2) com.vaadin:vaadin (>= 25.0.0, < 25.0.2) com.vaadin:vaadin (>= 24.0.0, < 24.9.8) com.vaadin:vaadin (>= 23.0.0, < 23.6.7) com.vaadin:vaadin (< 14.14.1)

Security releases

com.vaadin:flow-server → 14.14.1 (maven) com.vaadin:flow-server → 23.6.7 (maven) com.vaadin:flow-server → 24.9.8 (maven) com.vaadin:flow-server → 25.0.2 (maven) com.vaadin:vaadin → 25.0.2 (maven) com.vaadin:vaadin → 24.9.8 (maven) com.vaadin:vaadin → 23.6.7 (maven) com.vaadin:vaadin → 14.14.1 (maven)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

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Remediation advice

Upgrade the following packages to resolve this vulnerability:

com.vaadin:flow-server to 14.14.1 or later; com.vaadin:flow-server to 23.6.7 or later; com.vaadin:flow-server to 24.9.8 or later; com.vaadin:flow-server to 25.0.2 or later; com.vaadin:vaadin to 25.0.2 or later; com.vaadin:vaadin to 24.9.8 or later; com.vaadin:vaadin to 23.6.7 or later; com.vaadin:vaadin to 14.14.1 or later

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2026-2742? CVE-2026-2742 is a medium-severity security vulnerability in com.vaadin:flow-server (maven), affecting versions < 14.14.1. It is fixed in 14.14.1, 23.6.7, 24.9.8, 25.0.2.
Which packages are affected by CVE-2026-2742?
- com.vaadin:flow-server (maven) (versions < 14.14.1)
- com.vaadin:vaadin (maven) (versions >= 25.0.0, < 25.0.2)
Is there a fix for CVE-2026-2742? Yes. CVE-2026-2742 is fixed in 14.14.1, 23.6.7, 24.9.8, 25.0.2. Upgrade to this version or later.
Is CVE-2026-2742 exploitable, and should I be worried? Whether CVE-2026-2742 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether CVE-2026-2742 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix CVE-2026-2742?
- Upgrade com.vaadin:flow-server to 14.14.1 or later
- Upgrade com.vaadin:flow-server to 23.6.7 or later
- Upgrade com.vaadin:flow-server to 24.9.8 or later
- Upgrade com.vaadin:flow-server to 25.0.2 or later
- Upgrade com.vaadin:vaadin to 25.0.2 or later
- Upgrade com.vaadin:vaadin to 24.9.8 or later
- Upgrade com.vaadin:vaadin to 23.6.7 or later
- Upgrade com.vaadin:vaadin to 14.14.1 or later

Other vulnerabilities in com.vaadin:flow-server

CVE-IDSeverityPackage summary

CVE-2023-25499Mediumcom.vaadin:vaadin: Vaadin vulnerable to possible information disclosure in non visible components.CVE-2023-25500Lowcom.vaadin:flow-server: Vaadin vulnerable to possible information disclosure of class and method names in RPC response GHSA-FR26-QJC8-MVJXMediumcom.vaadin:flow-server: Possible route enumeration in production mode via RouteNotFoundError view in Vaadin 10, 11-14, and 15-19 GHSA-8VFW-V2JV-9HWCLowcom.vaadin:flow-server: Reflected cross-site scripting in development mode handler in Vaadin GHSA-C57F-4VP2-JQHMMediumcom.vaadin:flow-server: Insecure temporary directory usage in frontend build functionality of Vaadin 14 and 15-19