CVE-2025-15265

An SSR XSS exists in async hydration when attacker‑controlled keys are passed to hydratable. The key is embedded inside a <script> block without HTML‑safe escaping, allowing </script> to terminate the script and inject arbitrary JavaScript. This enables remote script execution in users' browsers, with potential for session theft and account compromise. This issue affects Svelte: from 5.46.0 before 5.46.3.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://fluidattacks.com/advisories/lydian	Exploit Third Party Advisory
https://fluidattacks.com/advisories/lydian	Exploit Third Party Advisory
https://github.com/sveltejs/svelte/security/advisories/GHSA-6738-r8g5-qwp3	Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

23 Jan 2026, 19:04

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.1
References	~~() https://fluidattacks.com/advisories/lydian -~~	() https://fluidattacks.com/advisories/lydian - Exploit, Third Party Advisory
References	~~() https://github.com/sveltejs/svelte/security/advisories/GHSA-6738-r8g5-qwp3 -~~	() https://github.com/sveltejs/svelte/security/advisories/GHSA-6738-r8g5-qwp3 - Third Party Advisory
First Time		Svelte svelte Svelte
CPE		cpe:2.3:a:svelte:svelte::::::node.js::*

15 Jan 2026, 20:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-15 20:16

Updated : 2026-01-23 19:04

NVD link : CVE-2025-15265

Mitre link : CVE-2025-15265

CVE.ORG link : CVE-2025-15265

JSON object : View

Products Affected

svelte

svelte

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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