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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
Passive
Minimal interaction
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products 3
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Svelte Svelte
cpe:2.3:a:svelte:svelte:*:*:windows:*:*:*:*:*
|
5.46.0
|
5.46.3
|
|
Svelte Svelte
cpe:2.3:a:svelte:svelte:*:*:linux:*:*:*:*:*
|
5.46.0
|
5.46.3
|
|
Svelte Svelte
cpe:2.3:a:svelte:svelte:*:*:macos:*:*:*:*:*
|
5.46.0
|
5.46.3
|