CVE-2025-15265 — MEDIUM (6.1)

Vulnerability Description

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 Score

6.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality

LOW

Integrity

LOW

Availability

NONE

Affected Products

Vendor	Product	Versions
Svelte	Svelte	>= 5.46.0, < 5.46.3

Related Weaknesses (CWE)

CWE-79

References

https://fluidattacks.com/advisories/lydianExploitThird Party Advisory
https://fluidattacks.com/advisories/lydianExploitThird Party Advisory
https://github.com/sveltejs/svelte/security/advisories/GHSA-6738-r8g5-qwp3Third Party Advisory

FAQ

What is CVE-2025-15265?

CVE-2025-15265 is a vulnerability with a CVSS score of 6.1 (MEDIUM). 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...

How severe is CVE-2025-15265?

CVE-2025-15265 has been rated MEDIUM with a CVSS base score of 6.1/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2025-15265?

Check the references section above for vendor advisories and patch information. Affected products include: Svelte Svelte.