CVE-2026-54298: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in withastro astro
Astro is a web framework. Prior to 6.4.6, the spreadAttributes function in Astro's server-side rendering pipeline iterates over object keys and passes them directly to addAttribute, which interpolates the key into the HTML output without escaping. When a developer uses the spread syntax {...props} on an HTML element and the object keys come from an untrusted source (API, CMS, URL parameters), an attacker can inject arbitrary HTML attributes including event handlers like onmousemove, onclick, or break out of the attribute context entirely to inject new elements. This vulnerability is fixed in 6.4.6.
AI Analysis
Technical Summary
CVE-2026-54298 is a cross-site scripting (CWE-79) vulnerability in the Astro web framework affecting versions before 6.4.6. The flaw exists in the spreadAttributes function of the server-side rendering pipeline, which interpolates object keys into HTML output without proper escaping. This improper neutralization of input allows attackers to inject arbitrary HTML attributes, including event handlers, when untrusted data is used with the spread syntax. The vulnerability is resolved in Astro version 6.4.6.
Potential Impact
An attacker can exploit this vulnerability to inject arbitrary HTML attributes, including event handlers, potentially leading to cross-site scripting attacks. The impact is limited to confidentiality and integrity as indicated by the CVSS vector (C:L/I:L/A:N). The attack requires network access with high attack complexity and user interaction.
Mitigation Recommendations
Upgrade to Astro version 6.4.6 or later, where this vulnerability is fixed. No other official remediation or temporary fixes are indicated. Patch status is confirmed by the version fix information.
CVE-2026-54298: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in withastro astro
Description
Astro is a web framework. Prior to 6.4.6, the spreadAttributes function in Astro's server-side rendering pipeline iterates over object keys and passes them directly to addAttribute, which interpolates the key into the HTML output without escaping. When a developer uses the spread syntax {...props} on an HTML element and the object keys come from an untrusted source (API, CMS, URL parameters), an attacker can inject arbitrary HTML attributes including event handlers like onmousemove, onclick, or break out of the attribute context entirely to inject new elements. This vulnerability is fixed in 6.4.6.
CVSS v3.1
Score 4.2medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-54298 is a cross-site scripting (CWE-79) vulnerability in the Astro web framework affecting versions before 6.4.6. The flaw exists in the spreadAttributes function of the server-side rendering pipeline, which interpolates object keys into HTML output without proper escaping. This improper neutralization of input allows attackers to inject arbitrary HTML attributes, including event handlers, when untrusted data is used with the spread syntax. The vulnerability is resolved in Astro version 6.4.6.
Potential Impact
An attacker can exploit this vulnerability to inject arbitrary HTML attributes, including event handlers, potentially leading to cross-site scripting attacks. The impact is limited to confidentiality and integrity as indicated by the CVSS vector (C:L/I:L/A:N). The attack requires network access with high attack complexity and user interaction.
Mitigation Recommendations
Upgrade to Astro version 6.4.6 or later, where this vulnerability is fixed. No other official remediation or temporary fixes are indicated. Patch status is confirmed by the version fix information.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-12T17:46:37.293Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a398861eed863c81e5021cb
Added to database: 06/22/2026, 19:09:21 UTC
Last enriched: 07/18/2026, 19:27:41 UTC
Last updated: 08/05/2026, 12:41:16 UTC
Views: 47
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