Summary
Two concurrent token-exchange requests using the same OAuth authorization code could
each mint a distinct valid (access_token, refresh_token) pair, breaking the
single-use guarantee that PKCE relies on.
Details
The token-exchange flow read is_used and called markAsUsed as an unconditional
update at the end of the path. A new OAuthAuthorizationCode.claimByCode method now
performs an atomic compare-and-swap (WHERE code = ? AND is_used = false) and is
called immediately before OAuthToken.insert, after redirect-URI, PKCE, and client
authentication have all succeeded. Only the first concurrent caller's UPDATE wins;
the rest see invalid_grant: Authorization code has already been used.
Credit
This issue was reported by @eddieran.
Impact
An attacker who has observed an authorization code and the corresponding PKCE
verifier (for example through a malicious OAuth-aware client or by racing a real
exchange) could obtain a long-lived refresh token in addition to the legitimate one.
Multiple concurrent operations access a shared resource without proper synchronization, producing unpredictable results depending on timing. Typical impact: TOCTOU exploits, data corruption, or privilege escalation.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2026-47386? CVE-2026-47386 is a medium-severity race condition vulnerability in nocodb (npm), affecting versions <= 2026.05.0. It is fixed in 2026.05.1. Multiple concurrent operations access a shared resource without proper synchronization, producing unpredictable results depending on timing.
- Which versions of nocodb are affected by CVE-2026-47386? nocodb (npm) versions <= 2026.05.0 is affected.
- Is there a fix for CVE-2026-47386? Yes. CVE-2026-47386 is fixed in 2026.05.1. Upgrade to this version or later.
- Is CVE-2026-47386 exploitable, and should I be worried? Whether CVE-2026-47386 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-47386 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-47386? Upgrade
nocodbto 2026.05.1 or later.