Thymeleaf is a server-side Java template engine for web and standalone environments. Prior to 3.1.5.RELEASE, a security bypass vulnerability exists in the expression execution mechanisms of Thymeleaf. Although the library provides mechanisms to avoid the execution of potentially dangerous expressions in some specific sandboxed (restricted) contexts, it fails to properly neutralize specific constructs that allow this kind of expressions to be executed. If an application developer passes to the template engine unsanitized variables that contain such expressions, and these values are used in sandboxed contexts inside the templates, these expressions can be executed achieving Server-Side Template Injection (SSTI). This vulnerability is fixed in 3.1.5.RELEASE.
History

Wed, 13 May 2026 00:30:00 +0000

Type Values Removed Values Added
First Time appeared Thymeleaf
Thymeleaf thymeleaf
Vendors & Products Thymeleaf
Thymeleaf thymeleaf

Tue, 12 May 2026 22:45:00 +0000

Type Values Removed Values Added
Description Thymeleaf is a server-side Java template engine for web and standalone environments. Prior to 3.1.5.RELEASE, a security bypass vulnerability exists in the expression execution mechanisms of Thymeleaf. Although the library provides mechanisms to avoid the execution of potentially dangerous expressions in some specific sandboxed (restricted) contexts, it fails to properly neutralize specific constructs that allow this kind of expressions to be executed. If an application developer passes to the template engine unsanitized variables that contain such expressions, and these values are used in sandboxed contexts inside the templates, these expressions can be executed achieving Server-Side Template Injection (SSTI). This vulnerability is fixed in 3.1.5.RELEASE.
Title Thymeleaf: Improper recognition of unauthorized syntax patterns in sandboxed Thymeleaf expressions
Weaknesses CWE-1336
CWE-917
References
Metrics cvssV3_1

{'score': 9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-12T22:35:50.617Z

Reserved: 2026-04-22T15:11:54.672Z

Link: CVE-2026-41901

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-05-12T23:16:17.060

Modified: 2026-05-12T23:16:17.060

Link: CVE-2026-41901

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-13T00:15:27Z