How severe is CVE-2021-41268?

CVE-2021-41268 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-41268 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41268?

CVE-2021-41268 affects Sensiolabs Symfony. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41268?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-41268 published?

CVE-2021-41268 was published on 2021-11-24 and last updated on 2026-06-17.

CVE-2021-41268

CVE-2021-41268 is a medium-severity vulnerability in Sensiolabs Symfony with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-384.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 6.5
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-384
Affected product: Sensiolabs Symfony
Published: 2021-11-24
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2021-41268?: CVE-2021-41268 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-41268 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41268?: CVE-2021-41268 affects Sensiolabs Symfony. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41268?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-41268 published?: CVE-2021-41268 was published on 2021-11-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:sensiolabs:symfony:*:*:*:*:*:*:*:*

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