CVE-2026-63462

HIGH
Published Aug 21, 2026 Modified Aug 25, 2026 CWE-674

Description

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.

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CVSS v3.1 Score

7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0048
Probability of exploitation
0.40%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-674 CWE-674

References

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-63462? +
CVE-2026-63462 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0048, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-63462? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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