CVE-2026-63462
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.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.5% chance of attack attempts being seen in the next 30 days, ranking above 40% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 7.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Weakness
- CWE-674
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-08-21
- Last modified
- 2026-09-09
- Sources
- NVD
References
- https://github.com/Unleash/unleash/commit/b0e4da63249a9403bc209e0581db223326cb8dcf
- https://github.com/Unleash/unleash/commit/d45f99df924c0d24747b3e45e46fcda7dcd3c1c1
- https://github.com/Unleash/unleash/commit/d862562a5ab8f2d1e40f6519c64cf0b4fdaf806d
- https://github.com/Unleash/unleash/releases/tag/v7.5.2
- https://github.com/Unleash/unleash/releases/tag/v7.6.5
- https://github.com/Unleash/unleash/releases/tag/v8.0.2
- https://github.com/Unleash/unleash/security/advisories/GHSA-r5pq-6chh-j3xp
- https://github.com/Unleash/unleash/security/advisories/GHSA-r5pq-6chh-j3xp