VulnerabilityAnalyzed

CVE-2026-27125

This vulnerability is fixed in 5.51.5.

MEDIUM 5.3EPSS 0.38%

Does this matter?

Lower severity and a low EPSS score (0.38%). Track it; it rarely justifies an emergency change on its own.

Description

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.

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:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.38% probability · 31th percentile
CISA KEV: Not listed
Weakness: CWE-915
Affected: svelte/svelte
Source: security-advisories@github.com

References

https://github.com/sveltejs/svelte/commit/73098bb26c6f06e7fd1b0746d817d2c5ee90755fPatch
https://github.com/sveltejs/svelte/releases/tag/svelte@5.51.5Product, Release Notes
https://github.com/sveltejs/svelte/security/advisories/GHSA-crpf-4hrx-3jrpVendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.