Bug 2538284 (CVE-2026-93981)

Summary: CVE-2026-93981 hono: hono/jsx: Cross-Site Scripting via Unescaped Strings
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: dschmidt, ikhan, jlanda, jwong, kshier, lchilton, omaciel, rbobbitt, rhel-process-autobot, rjohnson, sdawley, sfeifer, simaishi, stcannon, ttakamiy, watson-tool-maintainers, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in hono/jsx. This vulnerability occurs because the software fails to properly escape plain strings when they are rendered in certain contexts during server-side rendering. A remote attacker can exploit this by providing specially crafted input, leading to Cross-Site Scripting (XSS). This allows the attacker to inject malicious code into web pages viewed by other users, potentially compromising user sessions or defacing the website.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-09-22 17:35:37 UTC 
hono before 4.13.7 fails to HTML-escape plain strings rendered by hono/jsx as a child or fallback of Suspense, as a string child of ErrorBoundary alongside an asynchronous sibling, as the single child of a Context.Provider, or as the root value passed to renderToString() or renderToReadableStream() from hono/jsx/dom/server. These paths stringify their input and treat the result as already-escaped markup, so an attacker who controls such a string during server-side rendering can inject arbitrary HTML and execute script under the application's origin.