How severe is CVE-2026-54298?

CVE-2026-54298 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-54298 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-54298?

CVE-2026-54298 affects Astro. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-54298?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-54298 have an EU (EUVD) identifier?

Yes. CVE-2026-54298 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38336.

When was CVE-2026-54298 published?

CVE-2026-54298 was published on 2026-06-22 and last updated on 2026-06-23.

CVE-2026-54298

CVE-2026-54298 is a medium-severity vulnerability in Astro with a CVSS 3.x base score of 4.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 4.2)
EPSS exploit prediction: 0% (6th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-38336
Weakness: CWE-79
Affected product: Astro
Published: 2026-06-22
Last modified: 2026-06-23

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.

Frequently asked questions

What is CVE-2026-54298?: 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.
How severe is CVE-2026-54298?: CVE-2026-54298 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-54298 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-54298?: CVE-2026-54298 affects Astro. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-54298?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-54298 have an EU (EUVD) identifier?: Yes. CVE-2026-54298 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38336.
When was CVE-2026-54298 published?: CVE-2026-54298 was published on 2026-06-22 and last updated on 2026-06-23.

References

https://github.com/withastro/astro/security/advisories/GHSA-jrpj-wcv7-9fh9

Affected products (1)

cpe:2.3:a:astro:astro:*:*:*:*:*:node.js:*:*

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