Medium severity · published Aug 28, 2026
CVE-2026-82257
SvelteKit before 2.69.1 Prototype Pollution via File Input
4.3
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 29% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KI
kit · sveltejs
before 2.69.1 · source: vendor
SV
Sveltekit · Svelte
before 2.69.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-82257
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-82257
vendor-advisory
https://github.com/sveltejs/kit/security/advisories/GHSA-866w-xmhq-wj7x
third-party-advisory
https://www.vulncheck.com/advisories/sveltekit-before-2.69.1-prototype-pollution-via-file-input
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