CVE-2026-63462: Unleash

High severity, CVSS 7.5. EPSS: 0.7% chance of exploitation in the next 30 days.

Unleash is an open-source feature management platform. Prior to 7.5.2, 7.6.5, and 8.0.2, the shared OpenAPI validation error path in src/lib/error/bad-data-error.ts passes a raw request value from lodash.get to JSON.stringify in genericErrorMessage and fromOpenApiValidationErrors without guarding stack exhaustion. An unauthenticated attacker can send a roughly 10 KB JSON value nested thousands of levels deep to POST /edge/validate, POST /edge/issue-token, or another OpenAPI-validated endpoint, causing RangeError: Maximum call stack size exceeded in openAPIValidationMiddleware and terminating the Node process because no uncaughtException handler recovers it. Replaying the request can sustain a complete service outage. This issue is fixed in versions 7.5.2, 7.6.5, and 8.0.2.

Affected products

• Unleash Unleash: before 7.5.2 (fixed in 7.5.2); from 7.6.0, before 7.6.5 (fixed in 7.6.5); from 8.0.0, before 8.0.2 (fixed in 8.0.2)

Published 2026-08-21. Last modified 2026-09-09.