CVE-2021-31408

Local endpoint access via ineffective logout

Published Apr 23, 2021 · Updated Sep 17, 2024

Insufficient session expiration in Vaadin 18 and Vaadin 19.0.0 through 19.0.3 allows local attackers to retain Fusion endpoint access. The Authentication.logout() helper sends an HTTP GET request, so Spring Security CSRF protection rejects logout without invalidating the server session. Exploitation requires a Fusion application that uses the helper with logout CSRF protection enabled and a victim who attempts to log out, leaving the authenticated session available to the local attacker.

CVSS severity6.3
Medium
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Insufficient session expiration in Vaadin 18 and Vaadin 19.0.0 through 19.0.3 allows local attackers to retain Fusion endpoint access. The Authentication.logout() helper sends an HTTP GET request, so Spring Security CSRF protection rejects logout without invalidating the server session. Exploitation requires a Fusion application that uses the helper with logout CSRF protection enabled and a victim who attempts to log out, leaving the authenticated session available to the local attacker.

The record

CVE
CVE-2021-31408
Published
Apr 23, 2021
Updated
Sep 17, 2024
Vendor
Vaadin
Product
Vaadin Framework
Classifications
CWE-613
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 23, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=18.0.0 <* changes=[{"at":"19.0.0","status":"unaffected"},{"at":"19.0.0","status":"affected"}]

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Vaadin · Vaadin Frameworkversion=18.0.0 <* changes=[{"at":"19.0.0","status":"unaffected"},{"at":"19.0.0","status":"affected"}]
Vaadin · Vaadin Flowversion=5.0.0 <* changes=[{"at":"6.0.0","status":"unaffected"},{"at":"6.0.0","status":"affected"}]

Published CVSS scores

7.1NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
6.3VaadinCVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-613Insufficient Session Expiration

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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