mediumCVSS 4.3Vulnerability

GHSA-458j-xx4x-4375

## Summary Improper handling of JSX attribute names in hono/jsx allows malformed attribute keys to corrupt the generated HTML output. When untrusted input is used as attribute keys during server-side rendering, specially crafted keys can break out of attribute or tag boundaries and inject unintended HTML. ## Details When rendering JSX elements to HTML strings, attribute values are escaped, but attribute names (keys) were previously inserted into the output without validation. If an attribute name contains characters such as `"`, `>`, or whitespace, it can alter the structure of the generated HTML. For example, malformed attribute names can: * Break out of the current attribute and introduce unintended additional attributes * Break out of the current HTML tag and inject new elements into the output This issue arises when untrusted input (such as query parameters or form data) is used as JSX attribute keys during server-side rendering. ## Impact An attacker who can control attribute keys used in JSX rendering may inject unintended attributes or HTML elements into the generated output. This may lead to: * Injection of unexpected HTML attributes * Corruption of the HTML structure * Potential cross-site scripting (XSS) if combined with unsafe usage patterns This issue affects applications that pass untrusted input as JSX attribute keys during server-side rendering.

Properties

ghsa_id
GHSA-458j-xx4x-4375
severity
medium
summary
hono Improperly Handles JSX Attribute Names Allows HTML Injection in hono/jsx SSR
cvss_score
4.3
cve_id
GHSA-458j-xx4x-4375
cvss_vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
is_ghsa_only
true
ghsa_published
2026-04-16T01:02:24Z
source_url
https://github.com/advisories/GHSA-458j-xx4x-4375
ghsa_updated
2026-04-16T01:02:26Z

Related Entities (4)

REPORTED_BY (1)

[Source]GitHub Advisory Database

VULNERABLE_TO (1)

[Software]npm/hono

AFFECTS (1)

[Software]npm/hono

HAS_WEAKNESS (1)

[Weakness]Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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GHSA-458j-xx4x-4375 (CVSS 4.3) — Ninja Signal Threat Intelligence | Ninja Signal