CVE-2026-54298

What it is

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.

At a glance

Exploitability

Can be exploited over the network without logging in, but needs a user to act. Limited direct impact.

Exploit odds

0.2% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-06-22 19:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-10-25 23:10 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.2% in the next 30 days (EPSS).
• Severity: 4.2 MEDIUM (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2026-06-22 19:17 UTC

Last modified

2026-10-25 23:10 UTC

Exploit probability

0.2% · EPSS, next 30 days

Weakness

CWE-79 · Cross-site scripting

Record status

Modified

Affected

• Astro < 6.4.6

Attack profile CVSS 3.1 · 4.2

Attack vector

Network

Complexity

High

Privileges needed

None

User interaction

Required

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-54298.md and follow it. Check whether this project is affected by CVE-2026-54298. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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