CVE-2021-31409

mediumpriority · track · 31EPSS 0.017 · 77 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.67% (77th) EPSS

CVSS 5 · medium

Is it mine?

4 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

Unsafe validation RegEx in EmailValidator component in com.vaadin:vaadin-compatibility-server versions 8.0.0 through 8.12.4 (Vaadin versions 8.0.0 through 8.12.4) allows attackers to cause uncontrolled resource consumption by submitting malicious email addresses.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · security@vaadin.comexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · OSV

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USprimaryCWE-400US

affected products (4)

Products and version ranges known to be affected.

Vaadin Vaadin8.0.0 → *enisa_euvdEU
Vaadin vaadin-compatibility-server8.0.0 → *enisa_euvdEU
vaadin vaadin8.0.0 → 8.12.4nvdUScpe:2.3:a:vaadin:vaadin:*:*:*:*:*:*:*:*
Maven com.vaadin:vaadin-compatibility-server8.0.0 → 8.13.0osvUSpkg:maven/com.vaadin/vaadin-compatibility-server

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-c332-w4jm-55wvRegular expression Denial of Service (ReDoS) in EmailValidator class in V7 compatibility module in Vaadin 82021-05-04ghsa · osvUS
Unsafe validation RegEx in `EmailValidator` component in `com.vaadin:vaadin-compatibility-server` versions 8.0.0 through 8.12.4 (Vaadin versions 8.0.0 through 8.12.4) allows attackers to cause uncontrolled resource consumption by submitting malicious email addresses.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv NVD CVE.org MITRE

published 2021-05-06modified 2026-06-17

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+9607 more

references (10)

External citations — patches, advisories, analysis.

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