CVE-2021-31405: Regular expression denial of service (ReDoS) in EmailField component in Vaadin 14 and 15-17

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-04-23 · updated 2026-06-17
Weakness: CWE-400

Description

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.

Affected products

vaadin flow: from 2.0.4 before 2.3.3; from 3.0.0 before 4.0.3 — fixed in 2.3.3, 4.0.3
Vaadin: from 14.0.6 before 14.4.4; from 15.0.0 before 17.0.11 — fixed in 14.4.4, 17.0.11

How to fix

Upgrade to a fixed version: vaadin flow 2.3.3, 4.0.3; Vaadin 14.4.4, 17.0.11. Check the vendor advisory for mitigations.

References

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