Bug 2441520 (CVE-2026-27122)

Summary: CVE-2026-27122 svelte: Svelte SSR does not validate dynamic element tag names in `<svelte:element>`
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: medium    
Version: unspecifiedKeywords: Security
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OS: Linux   
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svelte is a performance oriented web framework. When using <svelte:element this={tag}> in server-side rendering, the provided tag name is not validated or sanitized before being emitted into the HTML output. If the tag string contains unexpected characters, it can result in HTML injection in the SSR output. Client-side rendering is not affected.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2441547, 2441551    
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Description OSIDB Bzimport 2026-02-20 23:01:57 UTC
svelte performance oriented web framework. Prior to 5.51.5, when using <svelte:element this={tag}> in server-side rendering, the provided tag name is not validated or sanitized before being emitted into the HTML output. If the tag string contains unexpected characters, it can result in HTML injection in the SSR output. Client-side rendering is not affected. This vulnerability is fixed in 5.51.5.