CVE-2021-21408: Access to restricted PHP code by dynamic static class access in smarty

Published Jan 10, 2022
·
Updated

Impact Template authors could run restricted static php methods.

Patches Please upgrade to 3.1.40 or higher.

References See the documentation on Smarty security features on the staticclasses access filter.

For more information If you have any questions or comments about this advisory please open an issue in the Smarty repo

Other sources

Access to restricted PHP code by dynamic static class access

Smarty is a template engine for PHP, facilitating the separation of presentation (HTML/CSS) from application logic. Prior to versions 3.1.43 and 4.0.3, template authors could run restricted static php methods. Users should upgrade to version 3.1.43 or 4.0.3 to receive a patch.

Affected Software

12 affected componentsFixes available
composer/smarty/smarty<3.1.43, >=4.0.0, <4.0.3
debian/smarty3
3.1.33+20180830.1.3a78a21f+selfpack1-1+deb10u13.1.33+20180830.1.3a78a21f+selfpack1-1+deb10u23.1.39-2+deb11u13.1.47-23.1.48-1
debian/smarty4
4.3.0-1+deb12u14.3.1-1
composer/smarty/smarty>=4.0.0<4.0.3
4.0.3
composer/smarty/smarty<3.1.43
3.1.43
Smarty smarty<3.1.43
Smarty smarty>=4.0.0<4.0.3
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0
Fedoraproject Fedora=36
Fedoraproject Fedora=37

Event History

Jan 10, 2022
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionSeverityWeakness
Advisory Published
10:48 AM
Apr 29, 2022
Data Sourced
08:57 PM
SeverityAffected Software
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2021-21408?

CVE-2021-21408 has been classified as a high-severity vulnerability due to its potential to allow unrestricted execution of static PHP methods.

2

How do I fix CVE-2021-21408?

To mitigate CVE-2021-21408, you should upgrade Smarty to version 3.1.40 or higher or 4.0.3.

3

Which versions of Smarty are affected by CVE-2021-21408?

CVE-2021-21408 affects versions of Smarty prior to 3.1.40 and those in the 4.0.0 to 4.0.3 range.

4

What type of vulnerability is CVE-2021-21408?

CVE-2021-21408 is a security vulnerability that allows template authors to execute restricted static PHP methods.

5

Where can I find more details about CVE-2021-21408?

Detailed information about CVE-2021-21408 can typically be found in the security advisories issued by Smarty.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203