hono - HTML Injection via Improper JSX Attribute Name Handling in SSR

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

hono before 4.12.14 contains an html injection vulnerability in jsx server-side rendering that allows attackers to inject unintended html by using malformed attribute names. Attackers can craft specially crafted attribute keys containing characters like quotes or angle brackets to break html tag boundaries and inject arbitrary attributes or elements.

Source published

24 Jun 2026 11:53:21 UTC

Source modified

24 Jun 2026 12:18:01 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 4.0 · 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS 3.1 · 4.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

hono before 4.12.14 contains an html injection vulnerability in jsx server-side rendering that allows attackers to inject unintended html by using malformed attribute names. Attackers can craft specially crafted attribute keys containing characters like quotes or angle brackets to break html tag boundaries and inject arbitrary attributes or elements.

Source published

Jun 24, 2026, 11:53:21 AM (timezone not stated)

Source modified

Jun 24, 2026, 12:18:01 PM (timezone not stated)

Observed here

7 Nov 2026 12:36:50 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 4.0 · 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

hono before 4.12.14 contains an html injection vulnerability in jsx server-side rendering that allows attackers to inject unintended html by using malformed attribute names. Attackers can craft specially crafted attribute keys containing characters like quotes or angle brackets to break html tag boundaries and inject arbitrary attributes or elements.

Source published

24 Jun 2026 13:16:37 UTC

Source modified

25 Oct 2026 23:10:00 UTC

Observed here

27 Oct 2026 15:15:18 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · [email protected] · Secondary · 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS 3.1 · [email protected] · Primary · 4.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

## 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.

Source published

16 Apr 2026 01:02:24 UTC

Source modified

10 Sep 2026 03:50:42 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Publisher rating · MODERATE