cve-2026-40477

CRITICAL CVSS 9.0 circl_kev
Description

Affected: Thymeleaf / Thymeleaf | 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. | Patched since: 2026/04/15 | Exploitation type: unknown | CWEs: CWE-917, CWE-1336 | Origin source: CNW | Notes: https://github.com/thymeleaf/thymeleaf/security/advisories/GHSA-r4v4-5mwr-2fwr

Timeline
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Last Modified
CVSS Details

CVSS details not available.

Affected Products

No product information available.

References

No references available.

Linked Vulnerabilities

No linked vulnerabilities found.

{
  "cvss": 9.0,
  "datePublished": "",
  "dateUpdated": "",
  "description": "Affected: Thymeleaf / Thymeleaf | 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. | Patched since: 2026/04/15 | Exploitation type: unknown | CWEs: CWE-917, CWE-1336 | Origin source: CNW | Notes: https://github.com/thymeleaf/thymeleaf/security/advisories/GHSA-r4v4-5mwr-2fwr",
  "dueDate": "",
  "exploited": true,
  "id": "CVE-2026-40477",
  "kev_catalogs": [
    "circl"
  ],
  "knownRansomwareCampaignUse": "",
  "product": "Thymeleaf",
  "severity": "CRITICAL",
  "source": "circl_kev",
  "title": "CVE-2026-40477",
  "vendor": "Thymeleaf"
}
Enrichment data
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