VulnerabilityAnalyzed
CVE-2025-15265
An SSR XSS exists in async hydration when attacker‑controlled keys are passed to hydratable.
MEDIUM 5.3EPSS 0.35%
Does this matter?
Lower severity and a low EPSS score (0.35%). Track it; it rarely justifies an emergency change on its own.
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 4.0
- 5.3 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.35% probability · 28th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- svelte/svelte
- Source
- help@fluidattacks.com
References
- https://fluidattacks.com/advisories/lydianExploit, Third Party Advisory
- https://fluidattacks.com/advisories/lydianExploit, Third Party Advisory
- https://fluidattacks.com/advisories/lydianExploit, Third Party Advisory
- https://fluidattacks.com/advisories/lydianExploit, Third Party Advisory
- https://github.com/sveltejs/svelte/security/advisories/GHSA-6738-r8g5-qwp3Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.