How severe is CVE-2026-82257?

CVE-2026-82257 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2026-82257 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-82257?

CVE-2026-82257 affects Svelte Sveltekit. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-82257?

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

When was CVE-2026-82257 published?

CVE-2026-82257 was published on 2026-08-28 and last updated on 2026-08-31.

CVE-2026-82257

CVE-2026-82257 is a medium-severity vulnerability in Svelte Sveltekit with a CVSS 3.x base score of 4.3. 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-1321.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v4: 5.3
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1321
Affected product: Svelte Sveltekit
Published: 2026-08-28
Last modified: 2026-08-31

Description

SvelteKit versions before 2.69.1 contain a prototype pollution vulnerability in remote form functions with file input fields that accept arbitrary user-controlled path names. Attackers can manipulate the deletion path to remove methods on the prototype, potentially disabling application functionality.

Frequently asked questions

What is CVE-2026-82257?: SvelteKit versions before 2.69.1 contain a prototype pollution vulnerability in remote form functions with file input fields that accept arbitrary user-controlled path names. Attackers can manipulate the deletion path to remove methods on the prototype, potentially disabling application functionality.
How severe is CVE-2026-82257?: CVE-2026-82257 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2026-82257 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-82257?: CVE-2026-82257 affects Svelte Sveltekit. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-82257?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-82257 published?: CVE-2026-82257 was published on 2026-08-28 and last updated on 2026-08-31.

References

Affected products (1)

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

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