Expression Language Injection Affecting thymeleaf package, versions *


Severity

Recommended
0.0
high
0
10

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.06% (18th percentile)

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  • Snyk IDSNYK-RHEL7-THYMELEAF-16118000
  • published21 Apr 2026
  • disclosed17 Apr 2026

Introduced: 17 Apr 2026

CVE-2026-40478  (opens in a new tab)
CWE-917  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:7 thymeleaf.

NVD Description

Note: Versions mentioned in the description apply only to the upstream thymeleaf package and not the thymeleaf package as distributed by RHEL. See How to fix? for RHEL:7 relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1