CVE-2026-42567

Svelte is a performance oriented web framework. From version 5.51.5 to before version 5.55.7, an internal regex in the Svelte runtime can take exponential time to test in <svelte:element this={tag}></svelte:element>. This issue has been patched in version 5.55.7.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7	Product Release Notes
https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:svelte:svelte:*:*:*:*:*:node.js:*:*

History

11 Jun 2026, 18:54

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
CPE		cpe:2.3:a:svelte:svelte::::::node.js::*
First Time		Svelte svelte Svelte
References	~~() https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7 -~~	() https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7 - Product, Release Notes
References	~~() https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6 -~~	() https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6 - Vendor Advisory

09 Jun 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-09 17:17

Updated : 2026-06-11 18:54

NVD link : CVE-2026-42567

Mitre link : CVE-2026-42567

CVE.ORG link : CVE-2026-42567

JSON object : View

Products Affected

svelte

svelte

CWE

CWE-1333

Inefficient Regular Expression Complexity

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