Summary
Timing side channel vulnerability in UIDL request handler in Vaadin 10, 11-14, and 15-18
Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:flow-server versions 1.0.0 through 1.0.13 (Vaadin 10.0.0 through 10.0.16), 1.1.0 prior to 2.0.0 (Vaadin 11 prior to 14), 2.0.0 through 2.4.6 (Vaadin 14.0.0 through 14.4.6), 3.0.0 prior to 5.0.0 (Vaadin 15 prior to 18), and 5.0.0 through 5.0.2 (Vaadin 18.0.0 through 18.0.5) allows attacker to guess a security token via timing attack.
Impact
GHSA-C6C4-7X48-4CQP has a CVSS score of 4.0 (Medium). The vector is requires local access, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (10.0.17, 14.4.7, 18.0.6); upgrading removes the vulnerable code path.
Affected versions
Security releases
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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com.vaadin:vaadin-bom to 10.0.17 or later; com.vaadin:vaadin-bom to 14.4.7 or later; com.vaadin:vaadin-bom to 18.0.6 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is GHSA-C6C4-7X48-4CQP? GHSA-C6C4-7X48-4CQP is a medium-severity security vulnerability in com.vaadin:vaadin-bom (maven), affecting versions >= 10.0.0, < 10.0.17. It is fixed in 10.0.17, 14.4.7, 18.0.6.
- How severe is GHSA-C6C4-7X48-4CQP? GHSA-C6C4-7X48-4CQP has a CVSS score of 4.0 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of com.vaadin:vaadin-bom are affected by GHSA-C6C4-7X48-4CQP? com.vaadin:vaadin-bom (maven) versions >= 10.0.0, < 10.0.17 is affected.
- Is there a fix for GHSA-C6C4-7X48-4CQP? Yes. GHSA-C6C4-7X48-4CQP is fixed in 10.0.17, 14.4.7, 18.0.6. Upgrade to this version or later.
- Is GHSA-C6C4-7X48-4CQP exploitable, and should I be worried? Whether GHSA-C6C4-7X48-4CQP 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 GHSA-C6C4-7X48-4CQP 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 GHSA-C6C4-7X48-4CQP?
- Upgrade
com.vaadin:vaadin-bomto 10.0.17 or later - Upgrade
com.vaadin:vaadin-bomto 14.4.7 or later - Upgrade
com.vaadin:vaadin-bomto 18.0.6 or later
- Upgrade