CVE-2026-44458: CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') in honojs hono
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.18, the JSX renderer escapes style attribute object values for HTML but not for CSS. Untrusted input in a style object value or property name can therefore inject additional CSS declarations into the rendered style attribute. The impact is limited to CSS and does not allow JavaScript execution or HTML attribute breakout. This vulnerability is fixed in 4.12.18.
AI Analysis
Technical Summary
The honojs hono framework versions before 4.12.18 contain a vulnerability where the JSX renderer escapes style attribute object values for HTML but not for CSS. This improper neutralization of special elements (CWE-74) allows an attacker to inject additional CSS declarations via untrusted input in style object values or property names. The impact is confined to CSS injection without enabling JavaScript execution or breaking out of HTML attributes. The issue is addressed in version 4.12.18.
Potential Impact
The vulnerability allows injection of additional CSS declarations through untrusted input in style attributes, which could affect the visual rendering of web pages. There is no impact on confidentiality, integrity, or availability beyond CSS injection, and no JavaScript execution or HTML attribute breakout is possible.
Mitigation Recommendations
Upgrade to honojs hono version 4.12.18 or later, where this vulnerability has been fixed. No other mitigation is indicated or required.
CVE-2026-44458: CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') in honojs hono
Description
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.18, the JSX renderer escapes style attribute object values for HTML but not for CSS. Untrusted input in a style object value or property name can therefore inject additional CSS declarations into the rendered style attribute. The impact is limited to CSS and does not allow JavaScript execution or HTML attribute breakout. This vulnerability is fixed in 4.12.18.
CVSS v3.1
Score 4.3medium
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The honojs hono framework versions before 4.12.18 contain a vulnerability where the JSX renderer escapes style attribute object values for HTML but not for CSS. This improper neutralization of special elements (CWE-74) allows an attacker to inject additional CSS declarations via untrusted input in style object values or property names. The impact is confined to CSS injection without enabling JavaScript execution or breaking out of HTML attributes. The issue is addressed in version 4.12.18.
Potential Impact
The vulnerability allows injection of additional CSS declarations through untrusted input in style attributes, which could affect the visual rendering of web pages. There is no impact on confidentiality, integrity, or availability beyond CSS injection, and no JavaScript execution or HTML attribute breakout is possible.
Mitigation Recommendations
Upgrade to honojs hono version 4.12.18 or later, where this vulnerability has been fixed. No other mitigation is indicated or required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-06T15:49:25.193Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a049721cbff5d8610e00edb
Added to database: 05/13/2026, 15:22:09 UTC
Last enriched: 05/20/2026, 18:46:32 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 79
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