CVE-2026-27125 (GCVE-0-2026-27125)

Vulnerability from cvelistv5 – Published: 2026-02-20 22:29 – Updated: 2026-02-20 22:29
VLAI?
Title
Svelte SSR attribute spreading includes inherited properties from prototype chain
Summary
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 ?
5.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:H/SI:H/SA:N
CWE
  • CWE-915 - Improperly Controlled Modification of Dynamically-Determined Object Attributes
Assigner
References
Impacted products
Vendor Product Version
sveltejs svelte Affected: < 5.51.5
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      "providerMetadata": {
        "dateUpdated": "2026-02-20T22:29:45.364Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
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      "source": {
        "advisory": "GHSA-crpf-4hrx-3jrp",
        "discovery": "UNKNOWN"
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      "title": "Svelte SSR attribute spreading includes inherited properties from prototype chain"
    }
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  "cveMetadata": {
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    "datePublished": "2026-02-20T22:29:45.364Z",
    "dateReserved": "2026-02-17T18:42:27.043Z",
    "dateUpdated": "2026-02-20T22:29:45.364Z",
    "state": "PUBLISHED"
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  }
}


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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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