How severe is CVE-2026-22803?

CVE-2026-22803 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-22803 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-22803?

CVE-2026-22803 affects Svelte Kit. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-22803?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-22803 have an EU (EUVD) identifier?

Yes. CVE-2026-22803 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2789.

When was CVE-2026-22803 published?

CVE-2026-22803 was published on 2026-01-15 and last updated on 2026-06-17.

CVE-2026-22803

CVE-2026-22803 is a high-severity vulnerability in Svelte Kit with a CVSS 3.x base score of 7.5. 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-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.2
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-2789
Weakness: CWE-770
Affected product: Svelte Kit
Published: 2026-01-15
Last modified: 2026-06-17

Description

SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From 2.49.0 to 2.49.4, the experimental form remote function uses a binary data format containing a representation of submitted form data. A specially-crafted payload can cause the server to allocate a large amount of memory, causing DoS via memory exhaustion. This vulnerability is fixed in 2.49.5.

Frequently asked questions

What is CVE-2026-22803?: SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From 2.49.0 to 2.49.4, the experimental form remote function uses a binary data format containing a representation of submitted form data. A specially-crafted payload can cause the server to allocate a large amount of memory, causing DoS via memory exhaustion. This vulnerability is fixed in 2.49.5.
How severe is CVE-2026-22803?: CVE-2026-22803 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-22803 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-22803?: CVE-2026-22803 affects Svelte Kit. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-22803?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-22803 have an EU (EUVD) identifier?: Yes. CVE-2026-22803 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2789.
When was CVE-2026-22803 published?: CVE-2026-22803 was published on 2026-01-15 and last updated on 2026-06-17.

References

Affected products (1)

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

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