CVE-2018-11406

Severity: high (CVSS 8.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-06-13 · updated 2026-06-17
Weakness: CWE-352

Description

An issue was discovered in the Security component in Symfony 2.7.x before 2.7.48, 2.8.x before 2.8.41, 3.3.x before 3.3.17, 3.4.x before 3.4.11, and 4.0.x before 4.0.11. By default, a user's session is invalidated when the user is logged out. This behavior can be disabled through the invalidate_session option. In this case, CSRF tokens were not erased during logout which allowed for CSRF token fixation.

Affected products

Debian Linux: 9.0
symfony: from 2.7.0 before 2.7.48; from 2.8.0 before 2.8.41; from 3.3.0 before 3.3.17; from 3.4.0 before 3.4.11; from 4.0.0 before 4.0.11 — fixed in 2.7.48, 2.8.41, 3.3.17, 3.4.11, 4.0.11

How to fix

Upgrade to a fixed version: symfony 2.7.48, 2.8.41, 3.3.17, 3.4.11. Check the vendor advisory for mitigations.

References

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