Vulnerability in Sensiolabs Symfony

CVE-2021-41268

Symfony/SecurityBundle is the security system for Symfony, a PHP framework for web and console applications and a set of reusable PHP components. Since the rework of the Remember me cookie in version 5.3.0, the cookie is not invalidated when the user changes their password. Attackers can therefore maintain their access to the account even if the password is changed as long as they have had the chance to login once and get a valid remember me cookie. Starting with version 5.3.12, Symfony makes the password part of the signature by default. In that way, when the password changes, then the cookie is not valid anymore.

EPSS: 0.013 (67.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-41268?
CVE-2021-41268 is a medium-severity vulnerability in Sensiolabs Symfony, classified under Session Fixation. CVSS score: 6.5/10. Published 2021-11-24.
How severe is CVE-2021-41268?
Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2021-41268 known to be exploited?
4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.