Vaadin Flow
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By the Year
In 2026 there have been 3 vulnerabilities in Vaadin Flow. Flow did not have any published security vulnerabilities last year. That is, 3 more vulnerabilities have already been reported in 2026 as compared to last year.
| Year | Vulnerabilities | Average Score |
|---|---|---|
| 2026 | 3 | 0.00 |
| 2025 | 0 | 0.00 |
| 2024 | 0 | 0.00 |
| 2023 | 0 | 0.00 |
| 2022 | 0 | 0.00 |
| 2021 | 11 | 5.26 |
It may take a day or so for new Flow vulnerabilities to show up in the stats or in the list of recent security vulnerabilities. Additionally vulnerabilities may be tagged under a different product or component name.
Recent Vaadin Flow Security Vulnerabilities
Vaadin Plugin Env Var Disclosure (fixed 23.6.10+)
CVE-2026-7860
- May 19, 2026
A possible information disclosure vulnerability exists in the Vaadin Maven plugin and Vaadin Gradle plugin that exposes the full set of environment variables in build logs whenever the frontend build process exits with a non-zero status. Because the build environment may contain credentials supplied as secrets, any failed frontend build can expose those secrets in clear text in CI logs and archived build artifacts. Users of affected versions should apply the following mitigation or upgrade. Releases that have fixed this issue include: Product version Vaadin 23.0.0 - 23.6.9 Vaadin 24.0.0 - 24.9.16 Vaadin 24.10.0 - 24.10.3 Vaadin 25.0.0 - 25.0.10 Vaadin 25.1.0 - 25.1.4 Mitigation Upgrade to 23.6.10 Upgrade to 24.9.17 or newer Upgrade to 24.10.4 or newer Upgrade to 25.0.11 or newer Upgrade to 25.1.5 or newer Please note that Vaadin versions 10-13 and 15-22 are no longer supported and you should update either to the latest 23, 24, or 25 version. ArtifactsMaven coordinatesVulnerable versionsFixed versioncom.vaadin:flow-plugin-base23.0.0 - 23.6.1023.6.11com.vaadin:flow-plugin-base24.0.0 - 24.9.1724.9.18com.vaadin:flow-plugin-base24.10.0 - 24.10.324.10.4com.vaadin:flow-plugin-base25.0.0 - 25.0.1125.0.12com.vaadin:flow-plugin-base25.1.0 - 25.1.425.1.5com.vaadin:flow-maven-plugin23.0.0 - 23.6.1023.6.11com.vaadin:flow-maven-plugin24.0.0 - 24.9.1724.9.18com.vaadin:flow-maven-plugin24.10.0 - 24.10.324.10.4com.vaadin:flow-maven-plugin25.0.0 - 25.0.1125.0.12com.vaadin:flow-maven-plugin25.1.0 - 25.1.425.1.5com.vaadin:flow-gradle-plugin24.0.0 - 24.9.1724.9.18com.vaadin:flow-gradle-plugin24.10.0 - 24.10.324.10.4com.vaadin:flow-gradle-plugin25.0.0 - 25.0.1125.0.12com.vaadin:flow-gradle-plugin25.1.0 - 25.1.425.1.5
Generation of Error Message Containing Sensitive Information
Vaadin Auth Bypass via /VAADIN endpoint in v14-25 (SpringSec)
CVE-2026-2742
- March 10, 2026
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 you should update either to the latest 14, 23, 24, 25 version.
Authorization
Vaadin 14.x-25.X Path Traversal in Node.js Download/Extraction (ZIP)
CVE-2026-2741
- March 10, 2026
Specially crafted ZIP archives can escape the intended extraction directory during Node.js download and extraction in Vaadin 14.2.0 through 14.14.0, 15.0.0 through 23.6.6, 24.0.0 through 24.9.8, and 25.0.0 through 25.0.2. Vaadins build process can automatically download and extract Node.js if it is not installed locally. If an attacker can intercept or control this download via DNS hijacking, a MITM attack, a compromised mirror, or a supply chain attack, they can serve a malicious archive containing path traversal sequences that write files outside the intended extraction directory. Users of affected versions should use a globally preinstalled Node.js version compatible with their Vaadin version, or upgrade as follows: 14.2.0-14.14.0 to 14.14.1, 15.0.0-23.6.6 to 23.6.7, 24.0.0-24.9.8 to 24.9.9, and 25.0.0-25.0.2 to 25.0.3 or newer. Please note that Vaadin versions 10-13 and 15-22 are no longer supported and you should update either to the latest 14, 23, 24, 25 version.
Directory traversal
Improper sanitization of path in default RouteNotFoundError view in com.vaadin:flow-server versions 1.0.0 through 1.0.14 (Vaadin 10.0.0 through 10.0.18), 1.1.0 prior to 2.0.0 (Vaadin 11 prior to 14), 2.0.0 through 2.6.1 (Vaadin 14.0.0 through 14.6.1), and 3.0.0 through 6.0.9 (Vaadin 15.0.0 through 19.0.8)
CVE-2021-31412
5.3 - Medium
- June 24, 2021
Improper sanitization of path in default RouteNotFoundError view in com.vaadin:flow-server versions 1.0.0 through 1.0.14 (Vaadin 10.0.0 through 10.0.18), 1.1.0 prior to 2.0.0 (Vaadin 11 prior to 14), 2.0.0 through 2.6.1 (Vaadin 14.0.0 through 14.6.1), and 3.0.0 through 6.0.9 (Vaadin 15.0.0 through 19.0.8) allows network attacker to enumerate all available routes via crafted HTTP request when application is running in production mode and no custom handler for NotFoundException is provided.
Improper Input Validation
Insecure temporary directory usage in frontend build functionality of com.vaadin:flow-server versions 2.0.9 through 2.5.2 (Vaadin 14.0.3 through Vaadin 14.5.2), 3.0 prior to 6.0 (Vaadin 15 prior to 19), and 6.0.0 through 6.0.5 (Vaadin 19.0.0 through 19.0.4)
CVE-2021-31411
7.8 - High
- May 05, 2021
Insecure temporary directory usage in frontend build functionality of com.vaadin:flow-server versions 2.0.9 through 2.5.2 (Vaadin 14.0.3 through Vaadin 14.5.2), 3.0 prior to 6.0 (Vaadin 15 prior to 19), and 6.0.0 through 6.0.5 (Vaadin 19.0.0 through 19.0.4) allows local users to inject malicious code into frontend resources during application rebuilds.
Authentication.logout() helper in com.vaadin:flow-client versions 5.0.0 prior to 6.0.0 (Vaadin 18), and 6.0.0 through 6.0.4 (Vaadin 19.0.0 through 19.0.3) uses incorrect HTTP method, which, in combination with Spring Security CSRF protection
CVE-2021-31408
7.1 - High
- April 23, 2021
Authentication.logout() helper in com.vaadin:flow-client versions 5.0.0 prior to 6.0.0 (Vaadin 18), and 6.0.0 through 6.0.4 (Vaadin 19.0.0 through 19.0.3) uses incorrect HTTP method, which, in combination with Spring Security CSRF protection, allows local attackers to access Fusion endpoints after the user attempted to log out.
Insufficient Session Expiration
Non-constant-time comparison of CSRF tokens in endpoint request handler in com.vaadin:flow-server versions 3.0.0 through 5.0.3 (Vaadin 15.0.0 through 18.0.6), and com.vaadin:fusion-endpoint version 6.0.0 (Vaadin 19.0.0)
CVE-2021-31406
2.5 - Low
- April 23, 2021
Non-constant-time comparison of CSRF tokens in endpoint request handler in com.vaadin:flow-server versions 3.0.0 through 5.0.3 (Vaadin 15.0.0 through 18.0.6), and com.vaadin:fusion-endpoint version 6.0.0 (Vaadin 19.0.0) allows attacker to guess a security token for Fusion endpoints via timing attack.
Side Channel Attack
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)
CVE-2021-31404
2.5 - Low
- April 23, 2021
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.
Side Channel Attack
Improper URL validation in development mode handler in com.vaadin:flow-server versions 2.0.0 through 2.4.1 (Vaadin 14.0.0 through 14.4.2), and 3.0 prior to 5.0 (Vaadin 15 prior to 18)
CVE-2020-36321
5.9 - Medium
- April 23, 2021
Improper URL validation in development mode handler in com.vaadin:flow-server versions 2.0.0 through 2.4.1 (Vaadin 14.0.0 through 14.4.2), and 3.0 prior to 5.0 (Vaadin 15 prior to 18) allows attacker to request arbitrary files stored outside of intended frontend resources folder.
Directory traversal
Vulnerability in OSGi integration in com.vaadin:flow-server versions 1.2.0 through 2.4.7 (Vaadin 12.0.0 through 14.4.9), and 6.0.0 through 6.0.1 (Vaadin 19.0.0)
CVE-2021-31407
7.5 - High
- April 23, 2021
Vulnerability in OSGi integration in com.vaadin:flow-server versions 1.2.0 through 2.4.7 (Vaadin 12.0.0 through 14.4.9), and 6.0.0 through 6.0.1 (Vaadin 19.0.0) allows attacker to access application classes and resources on the server via crafted HTTP request.
Exposure of Resource to Wrong Sphere
Missing output sanitization in default RouteNotFoundError view in com.vaadin:flow-server versions 1.0.0 through 1.0.10 (Vaadin 10.0.0 through 10.0.13), and 1.1.0 through 1.4.2 (Vaadin 11.0.0 through 13.0.5)
CVE-2019-25027
6.1 - Medium
- April 23, 2021
Missing output sanitization in default RouteNotFoundError view in com.vaadin:flow-server versions 1.0.0 through 1.0.10 (Vaadin 10.0.0 through 10.0.13), and 1.1.0 through 1.4.2 (Vaadin 11.0.0 through 13.0.5) allows attacker to execute malicious JavaScript via crafted URL
Improper Neutralization of Script in an Error Message Web Page
Insecure configuration of default ObjectMapper in com.vaadin:flow-server versions 3.0.0 through 3.0.5 (Vaadin 15.0.0 through 15.0.4) may expose sensitive data if the application also uses e.g
CVE-2020-36319
3.1 - Low
- April 23, 2021
Insecure configuration of default ObjectMapper in com.vaadin:flow-server versions 3.0.0 through 3.0.5 (Vaadin 15.0.0 through 15.0.4) may expose sensitive data if the application also uses e.g. @RestController
Information Disclosure
Missing check in UIDL request handler in com.vaadin:flow-server versions 1.0.0 through 1.0.5 (Vaadin 10.0.0 through 10.0.7, and 11.0.0 through 11.0.2)
CVE-2018-25007
2.6 - Low
- April 23, 2021
Missing check in UIDL request handler in com.vaadin:flow-server versions 1.0.0 through 1.0.5 (Vaadin 10.0.0 through 10.0.7, and 11.0.0 through 11.0.2) allows attacker to update element property values via crafted synchronization message.
Improper Check for Unusual or Exceptional Conditions
Unsafe validation RegEx in EmailField component in com.vaadin:vaadin-text-field-flow versions 2.0.4 through 2.3.2 (Vaadin 14.0.6 through 14.4.3), and 3.0.0 through 4.0.2 (Vaadin 15.0.0 through 17.0.10)
CVE-2021-31405
7.5 - High
- April 23, 2021
Unsafe validation RegEx in EmailField component in com.vaadin:vaadin-text-field-flow versions 2.0.4 through 2.3.2 (Vaadin 14.0.6 through 14.4.3), and 3.0.0 through 4.0.2 (Vaadin 15.0.0 through 17.0.10) allows attackers to cause uncontrolled resource consumption by submitting malicious email addresses.
Resource Exhaustion
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