VYPR
Critical severity9.0NVD Advisory· Published Apr 17, 2026· Updated Apr 24, 2026

CVE-2026-40478

CVE-2026-40478

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.

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Affected packages

Versions sourced from the GitHub Security Advisory.

PackageAffected versionsPatched versions
org.thymeleaf:thymeleafMaven
< 3.1.4.RELEASE3.1.4.RELEASE
org.thymeleaf:thymeleaf-spring5Maven
< 3.1.4.RELEASE3.1.4.RELEASE
org.thymeleaf:thymeleaf-spring6Maven
< 3.1.4.RELEASE3.1.4.RELEASE

Affected products

4

Patches

Vulnerability mechanics

References

3

News mentions

0

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