CVE-2021-21408— Access to restricted PHP code by dynamic static class access in smarty
Quick assessment
Affected
smarty-php smarty
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Smarty是Smarty 是 PHP 的模板引擎，有助于将表示 (HTML/CSS) 与应用程序逻辑分离。 Smarty存在安全漏洞，该漏洞源于Smarty是PHP的一个模板引擎，它促进了表示(HTML CSS)与应用逻辑的分离。在3.1.43和4.0.3版本之前，模板作者可以运行受限的静态php方法。用户应该升级到3.1.43或4.0.3版本来接收补丁。
Possible ATT&CK Techniques 1 AI
T1190 · Exploit Public-Facing Application
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I. Basic Information for CVE-2021-21408
Vulnerability Information
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Vulnerability Title
Access to restricted PHP code by dynamic static class access in smarty
Source: CVE Program / CVE List V5
Vulnerability Description
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.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
输入验证不恰当
Source: CVE Program / CVE List V5
Vulnerability Title
Smarty 输入验证错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Smarty是Smarty 是 PHP 的模板引擎，有助于将表示 (HTML/CSS) 与应用程序逻辑分离。 Smarty存在安全漏洞，该漏洞源于Smarty是PHP的一个模板引擎，它促进了表示(HTML CSS)与应用逻辑的分离。在3.1.43和4.0.3版本之前，模板作者可以运行受限的静态php方法。用户应该升级到3.1.43或4.0.3版本来接收补丁。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| smarty-php | smarty | < 3.1.43 | - |
|
II. Public POCs for CVE-2021-21408
| # | POC Description | Source Link | Shenlong Link |
|---|
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Patches & Fixes for CVE-2021-21408 (1)
Vendor Advisories for CVE-2021-21408 (3)
-
https://www.debian.org/security/2022/dsa-5151 vendor-advisory
-
https://security.gentoo.org/glsa/202209-09 vendor-advisory
Mailing List Discussions for CVE-2021-21408 (3)
IV. Related Vulnerabilities
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Same weakness: CWE-20
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V. Comments for CVE-2021-21408
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