CVE-2021-31403
Timing side channel vulnerability in UIDL request handler in Vaadin 7 and 8
Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:vaadin-server versions 7.0.0 through 7.7.23 (Vaadin 7.0.0 through 7.7.23), and 8.0.0 through 8.12.2 (Vaadin 8.0.0 through 8.12.2) allows attacker to guess a security token via timing attack
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Timing side channel vulnerability in UIDL request handler in Vaadin 7 and 8
Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:vaadin-server versions 7.0.0 through 7.7.23 (Vaadin 7.0.0 through 7.7.23), and 8.0.0 through 8.12.2 (Vaadin 8.0.0 through 8.12.2) allows attacker to guess a security token via timing attack
- Record
CVE-2021-31403- CVSS 3.1
- 4.0 Medium
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-208
- Updated
- 2026-11-02
EUVDEUVD-2021-0784
Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:vaadin-server versions 7.0.0 through 7.7.23 (Vaadin 7.0.0 through 7.7.23), and 8.0.0 through 8.12.2 (Vaadin 8.0.0 through 8.12.2) allows attacker to guess a security token via timing attack
- Record
EUVD-2021-0784- CVSS 3.1
- 4.0 Medium
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-75xc-qvxh-27f8
Timing side channel vulnerability in UIDL request handler in Vaadin 7 and 8
Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:vaadin-server versions 7.0.0 through 7.7.23 (Vaadin 7.0.0 through 7.7.23), and 8.0.0 through 8.12.2 (Vaadin 8.0.0 through 8.12.2) allows attacker to guess a security token via timing attack
- Record
GHSA-75xc-qvxh-27f8- CVSS 3.1
- 4.0 Medium
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-203, CWE-208
- Updated
- 2026-11-02
NVD
Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:vaadin-server versions 7.0.0 through 7.7.23 (Vaadin 7.0.0 through 7.7.23), and 8.0.0 through 8.12.2 (Vaadin 8.0.0 through 8.12.2) allows attacker to guess a security token via timing attack
- Record
CVE-2021-31403- CVSS 3.1
- 4.0 Medium
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - CVSS 3.1
- 2.5 Low
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N - CVSS 2.0
- 1.9 Low
AV:L/AC:M/Au:N/C:P/I:N/A:N - Weakness
- CWE-208, CWE-203
- Updated
- 2026-11-02
OSV
Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:vaadin-server versions 7.0.0 through 7.7.23 (Vaadin 7.0.0 through 7.7.23), and 8.0.0 through 8.12.2 (Vaadin 8.0.0 through 8.12.2) allows attacker to guess a security token via timing attack
- Record
CVE-2021-31403- CVSS 3.1
- 2.5 Low
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVGHSA-75xc-qvxh-27f8
Timing side channel vulnerability in UIDL request handler in Vaadin 7 and 8
Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:vaadin-server versions 7.0.0 through 7.7.23 (Vaadin 7.0.0 through 7.7.23), and 8.0.0 through 8.12.2 (Vaadin 8.0.0 through 8.12.2) allows attacker to guess a security token via timing attack
- Record
GHSA-75xc-qvxh-27f8- CVSS 3.1
- 4.0 Medium
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-203, CWE-208
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
com.vaadin:vaadin-bomMaven |
7.0.0 up to 7.7.24 | 7.7.24 |
com.vaadin:vaadin-bomMaven |
8.0.0 up to 8.12.3 | 8.12.3 |
com.vaadin:vaadin-serverMaven |
7.0.0 up to 7.7.24 | 7.7.24 |
com.vaadin:vaadin-serverMaven |
8.0.0 up to 8.12.3 | 8.12.3 |
com.vaadin:vaadin-bomMaven |
7.0.0 up to 7.7.24, plus listed versions 7.4.07.4.17.4.27.4.37.4.4 Show 45 moreShow less7.4.57.4.67.4.77.4.87.5.07.5.0.beta17.5.0.beta27.5.0.beta37.5.0.rc17.5.0.rc27.5.17.5.107.5.27.5.37.5.47.5.57.5.67.5.77.5.87.5.97.6.07.6.0.alpha17.6.0.alpha27.6.17.6.27.6.37.6.47.6.57.6.67.6.77.6.87.7.07.7.17.7.107.7.117.7.127.7.137.7.147.7.157.7.167.7.177.7.27.7.237.7.37.7.4 |
7.7.24 |
com.vaadin:vaadin-bomMaven |
8.0.0 up to 8.12.3, plus listed versions 8.0.18.0.28.0.38.0.48.0.5 Show 45 moreShow less8.0.68.0.78.1.08.1.18.1.28.1.38.1.48.1.58.1.68.1.78.1.88.10.08.10.18.10.28.10.38.10.48.10.58.11.08.11.18.11.28.11.38.12.08.12.18.12.28.2.08.2.18.3.08.3.18.3.28.3.38.4.08.4.18.4.28.4.38.4.48.4.58.5.08.5.18.5.28.6.08.6.18.6.28.6.38.6.48.7.0 |
8.12.3 |
com.vaadin:vaadin-serverMaven |
7.0.0 up to 7.7.24, plus listed versions 7.0.17.0.27.0.37.0.47.0.5 Show 45 moreShow less7.0.67.0.77.1.07.1.0.beta17.1.17.1.107.1.117.1.127.1.137.1.147.1.157.1.27.1.37.1.47.1.57.1.67.1.77.1.87.1.97.2.07.2.0.beta17.2.17.2.27.2.37.2.47.2.57.2.67.2.77.3.07.3.0.alpha17.3.0.alpha27.3.0.alpha37.3.0.beta17.3.0.rc17.3.17.3.107.3.27.3.37.3.47.3.57.3.67.3.77.3.87.3.97.4.0 |
7.7.24 |
com.vaadin:vaadin-serverMaven |
8.0.0 up to 8.12.3, plus listed versions 8.0.18.0.28.0.38.0.48.0.5 Show 45 moreShow less8.0.68.0.78.1.08.1.18.1.28.1.38.1.48.1.58.1.68.1.78.1.88.10.08.10.18.10.28.10.38.10.48.10.58.11.08.11.18.11.28.11.38.12.08.12.18.12.28.2.08.2.18.3.08.3.18.3.28.3.38.4.08.4.18.4.28.4.38.4.48.4.58.5.08.5.18.5.28.6.08.6.18.6.28.6.38.6.48.7.0 |
8.12.3 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-31403 is a medium vulnerability (CVSS 4.0) in Vaadin, published April 19, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.31%, the 23rd percentile. Fixed in com.vaadin:vaadin-bom 7.7.24.
References
Left out here: 108 versions. The JSON record has them.