CVE-2026-40073
SvelteKit <= 2.57.0 bypasses BODY_SIZE_LIMIT on adapter-node.
Is CVE-2026-40073 being exploited?
Not confirmed. CVE-2026-40073 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.54% probability of exploitation in the next 30 days.
How severe is CVE-2026-40073?
CVE-2026-40073 is rated High with a CVSS score of 8.2. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-40073?
Yes. A fix has been recorded for CVE-2026-40073. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-40073 affect?
CVE-2026-40073 affects SvelteKit (pre-2.57.1), adapter-node deployments. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-40073?
Upgrade to 2.57.1 or newer
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Bypass body size checks, enabling oversized requests; risk of resource exhaustion and possible RCE in vulnerable apps.
Patch when possible
- affected< 2.57.1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.