Timing side channel vulnerability in UIDL request handler in Vaadin 10, 11-14, and 15-18
Published Apr 23, 2021 · Updated Oct 23, 2026 · Also known as GHSA-xwg3-qrcg-w9x6
Original summary
Normalized public record · Updated Oct 23, 2026
Timing side channel vulnerability in UIDL request handler in Vaadin 10, 11-14, and 15-18
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
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 through 13), 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.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- LOW
- Confidence
- Not available
- Aliases
- GHSA-xwg3-qrcg-w9x6
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
Record history
Published Apr 23, 2021 · Last refreshed Oct 23, 2026