How severe is CVE-2026-42573?

CVE-2026-42573 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-42573 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-42573?

CVE-2026-42573 affects Svelte. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-42573?

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

Does CVE-2026-42573 have an EU (EUVD) identifier?

Yes. CVE-2026-42573 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35701.

When was CVE-2026-42573 published?

CVE-2026-42573 was published on 2026-06-09 and last updated on 2026-06-30.

CVE-2026-42573

CVE-2026-42573 is a medium-severity vulnerability in Svelte with a CVSS 3.x base score of 6.1. 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 6.1)
CVSS v4: 5.3
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-35701
Weakness: CWE-79
Affected product: Svelte
Published: 2026-06-09
Last modified: 2026-06-30

Description

Svelte is a performance oriented web framework. Prior to version 5.55.7, Svelte was vulnerable to DOM clobbering of its internal framework state on elements, potentially leading to XSS attacks. This issue has been patched in version 5.55.7.

Frequently asked questions

What is CVE-2026-42573?: Svelte is a performance oriented web framework. Prior to version 5.55.7, Svelte was vulnerable to DOM clobbering of its internal framework state on elements, potentially leading to XSS attacks. This issue has been patched in version 5.55.7.
How severe is CVE-2026-42573?: CVE-2026-42573 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-42573 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-42573?: CVE-2026-42573 affects Svelte. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-42573?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-42573 have an EU (EUVD) identifier?: Yes. CVE-2026-42573 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35701.
When was CVE-2026-42573 published?: CVE-2026-42573 was published on 2026-06-09 and last updated on 2026-06-30.

References

Affected products (1)

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

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