CVE-2026-82258 — @sveltejs/kit
Fix: sveltejs/kit@dadaefcCVE-2026-82258 is a CWE-362 vulnerability in @sveltejs/kit. A fix is available for @sveltejs/kit — see the affected versions and patch details below.
SvelteKit 2.38.0 before 2.60.1 Cross-User Data Disclosure via query.batch
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-82258.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@sveltejs/kitnpmDescription
SvelteKit versions from 2.38.0 before 2.60.1 contain a race condition in query.batch that allows concurrent requests from different users to merge under a single request context. Attackers can exploit specific timing conditions to access sensitive data from other users' concurrent requests.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @sveltejs/kit | ≥ 2.38.0&&< 2.60.1 | 2.60.1npm install @sveltejs/kit@2.60.1 |
Affected Products
sveltekitsvelteDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @sveltejs/kit, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @sveltejs/kit to 2.60.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-82258 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2026-82258 in your dependencies?
Find it across npm, including transitive dependencies.