CVE-2026-40477

CRITICAL EPSS 46.5%
Published Apr 17, 20262mo ago · Modified Jun 17, 20262w ago
9.0 CVSS 3.1
Critical
Find Similar
Published Apr 17, 2026 2mo ago
Last Modified Jun 17, 2026 2w ago

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 expression execution mechanisms. Although the library provides mechanisms to prevent expression injection, it fails to properly restrict the scope of accessible objects, allowing specific potentially sensitive objects to be reached from within a template. 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 Details

Base Score
9.0
Exploitability
2.2
Impact
6.0
Vector string
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope Changed
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
46.5% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 2

CWE-1336
CWE-917

Affected Products 1

VendorProductVersionRange
thymeleafthymeleaf* <3.1.4

References 1

  • github.com https://github.com/thymeleaf/thymeleaf/security/advisories/GHSA-r4v4-5mwr-2fwr
    Vendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.