CVE-2026-40478criticalCWE-1336CWE-917

CVE-2026-40478: fallo crítico en thymeleaf

Improper neutralization of specific syntax patterns for unauthorized expressions in Thymeleaf

Publicada el · Actualizada el

28Vexday Risk Score

Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.

ssvc Trackcvss 9.1epss 1.1%
probabilidad de explotación
1.1%top 34% de las CVE
explotación observada
noninguna fuente lo reporta
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:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Productos afectados
thymeleaf · org.thymeleaf:thymeleaf-spring5thymeleaf · org.thymeleaf:thymeleaf-spring6thymeleaf · thymeleaf
CVEs relacionadas — thymeleaf

En el mismo producto, de las más peligrosas a las menos.

CVE-2026-40477CRITICALImproper restriction of the scope of accessible objects in Thymeleaf expressionsEPSS 0.9%CVE-2026-41901CRITICALThymeleaf: Improper recognition of unauthorized syntax patterns in sandboxed Thymeleaf expressionsEPSS 0.4%
Referencias
https://access.redhat.com/errata/RHSA-2026:21772https://access.redhat.com/security/cve/CVE-2026-40478https://bugzilla.redhat.com/show_bug.cgi?id=2459349https://github.com/thymeleaf/thymeleaf/security/advisories/GHSA-xjw8-8c5c-9r79https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40478.json