CVSS 4.0
5.3 mediumCVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:H/SI:H/SA:NCVE-2026-27125
Medium (5.3) in svelte svelte. EPSS 0.4% chance of exploitation in the next 30 days. Fixed in svelte 5.51.5.
svelte performance oriented web framework. Prior to 5.51.5, in server-side rendering, attribute spreading on elements (e.g. <div {...attrs}>) enumerates inherited properties from the object's prototype chain rather than only own properties. In environments where Object.prototype has already been polluted — a precondition outside of Svelte's control — this can cause unexpected attributes to appear in SSR output or cause SSR to throw errors. Client-side rendering is not affected. This vulnerability is fixed in 5.51.5.
Severity
CVSS 3.1
6.8 mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N- EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 37% of CVEs (scores of 2026-10-31)
- CWE
- CWE-915
- Published
- Modified
- Record from
- the NVD, synced
Affected
- svelte:svelte
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-crpf-4hrx-3jrp | npm | svelte | <5.51.5 | 5.51.5 |