CVE-2026-31866
7.5 · HIGHOverview
CVE-2026-31866 is a high-severity vulnerability affecting openfeature flagd. It was published on March 11, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
flagd is a feature flag daemon with a Unix philosophy. Prior to 0.14.2, flagd exposes OFREP (/ofrep/v1/evaluate/...) and gRPC (evaluation.v1, evaluation.v2) endpoints for feature flag evaluation. These endpoints are designed to be publicly accessible by client applications. The evaluation context included in request payloads is read into memory without any size restriction. An attacker can send a single HTTP request with an arbitrarily large body, causing flagd to allocate a corresponding amount of memory. This leads to immediate memory exhaustion and process termination (e.g., OOMKill in Kubernetes environments). flagd does not natively enforce authentication on its evaluation endpoints. While operators may deploy flagd behind an authenticating reverse proxy or similar infrastructure, the endpoints themselves impose no access control by default. This vulnerability is fixed in 0.14.2.
Remediation
Check the references section for vendor advisories and patches from openfeature. Update flagd to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| openfeature | flagd | >= 0, < 0.14.2 | Affected |
Frequently Asked Questions
What is CVE-2026-31866?
CVE-2026-31866 is a high-severity vulnerability affecting openfeature flagd. It was published on March 11, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-31866?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-31866?
Check the references section for vendor advisories and patches from openfeature. Update flagd to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-31866?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-31866 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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