CVE-2026-40478
Published: Apr 17, 2026
Modified: Apr 22, 2026
CVSS v3.1
9.1
Description
Thymeleaf is a server-side Java template engine for web and standalone environments. Versions 3.1.3.RELEASE and prior contain a security bypass vulnerability in the the expression execution mechanisms. Although the library provides mechanisms to prevent expression injection, it fails to properly neutralize specific syntax patterns that allow for the execution of unauthorized expressions. If an application developer passes unvalidated user input directly to the template engine, an unauthenticated remote attacker can bypass the library's protections to achieve Server-Side Template Injection (SSTI). This issue has ben fixed in version 3.1.4.RELEASE.
| Vendor | Product | Versions |
|---|---|---|
thymeleaf | thymeleaf | affected < 3.1.4.RELEASE |
thymeleaf | org.thymeleaf:thymeleaf-spring5 | affected < 3.1.4.RELEASE |
thymeleaf | org.thymeleaf:thymeleaf-spring6 | affected < 3.1.4.RELEASE |
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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