CVE-2021-26120

Name: CVE-2021-26120
Creator: NVD / NIST
Published: 2021-02-22T02:15:14.323+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 82.32%

Last modified Jun 17, 2026

CVE-2021-26120 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Smarty before 3.1.39 allows code injection via an unexpected function name after a {function name= substring.. EPSS estimates a 82.32% chance of exploitation in the next 30 days.

Description

Smarty before 3.1.39 allows code injection via an unexpected function name after a {function name= substring.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

82.32%

99.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-94

Affected Software

Vendor	Product	Versions
Smarty	Smarty	< 3.1.39
Debian	Debian Linux	9.0
Debian	Debian Linux	10.0
Debian	Debian Linux	11.0

References

https://github.com/smarty-php/smarty/blob/master/CHANGELOG.mdRelease Notes, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/04/msg00004.htmlMailing List, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/04/msg00014.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/202105-06Patch, Third Party Advisory
https://www.debian.org/security/2022/dsa-5151Third Party Advisory
https://github.com/smarty-php/smarty/blob/master/CHANGELOG.mdRelease Notes, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/04/msg00004.htmlMailing List, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/04/msg00014.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/202105-06Patch, Third Party Advisory
https://www.debian.org/security/2022/dsa-5151Third Party Advisory

Timeline

Published: Feb 22, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-26120?

Smarty before 3.1.39 allows code injection via an unexpected function name after a {function name= substring.

How severe is CVE-2021-26120?

CVE-2021-26120 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 82.32% probability of exploitation in the next 30 days.

How do I fix CVE-2021-26120?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-26120?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST