Quick answers
- Is CVE-2026-82261 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-82261 being exploited in the wild.
- How severe is CVE-2026-82261?
- High severity, with a CVSS score of 7.5, published 28 August 2026.
- Which products and versions are affected?
- @sveltejs/kit (npm) SEMVER:introduced=2.49.0,fixed=2.52.2; SvelteKit 2.49.0 to 2.52.1.
- Is there a fix for CVE-2026-82261?
- Yes. @sveltejs/kit (npm): upgrade to 2.52.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-82261 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-82261?
- Check whether you run @sveltejs/kit (npm) or SvelteKit at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- @sveltejs/kit (npm): upgrade to 2.52.2 or later
npm install @sveltejs/kit@2.52.2
Technical details
This vulnerability is a denial-of-service condition triggered by insufficient validation of form file metadata in SvelteKit's deserialization logic. When the experimental.remoteFunctions and form features are both enabled, an attacker can send malformed form data that causes the server to enter an amplification/CPU exhaustion state during the devalue.parse() operation. The attack is network-reachable and requires no authentication or user interaction. An attacker can craft requests that make the server unresponsive while processing, denying service to legitimate users. The fix was released in version 2.52.2 and involves validating form file information to prevent amplification attacks.
Affected products
- Svelte SvelteKit 2.49.0 to 2.52.1
Identifiers
- CVE-2026-82261
- GHSA-88qp-p4qg-rqm6
Timeline
- 2026-02-19: disclosed
- 2026-02-18: patched: Fixed in version 2.52.2