GHSA-8M7C-HF24-5G47
Vulnerability from github – Published: 2026-06-05 16:20 – Updated: 2026-07-20 21:18Summary
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.
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.
Credit
This issue was reported by @eddieran.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 2026.05.0"
},
"package": {
"ecosystem": "npm",
"name": "nocodb"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2026.05.1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-47386"
],
"database_specific": {
"cwe_ids": [
"CWE-362"
],
"github_reviewed": true,
"github_reviewed_at": "2026-06-05T16:20:32Z",
"nvd_published_at": "2026-06-23T21:17:00Z",
"severity": "MODERATE"
},
"details": "### Summary\nTwo concurrent token-exchange requests using the same OAuth authorization code could\neach mint a distinct valid `(access_token, refresh_token)` pair, breaking the\nsingle-use guarantee that PKCE relies on.\n\n### Details\nThe token-exchange flow read `is_used` and called `markAsUsed` as an unconditional\nupdate at the end of the path. A new `OAuthAuthorizationCode.claimByCode` method now\nperforms an atomic compare-and-swap (`WHERE code = ? AND is_used = false`) and is\ncalled immediately before `OAuthToken.insert`, after redirect-URI, PKCE, and client\nauthentication have all succeeded. Only the first concurrent caller\u0027s `UPDATE` wins;\nthe rest see `invalid_grant: Authorization code has already been used`.\n\n### Impact\nAn attacker who has observed an authorization code and the corresponding PKCE\nverifier (for example through a malicious OAuth-aware client or by racing a real\nexchange) could obtain a long-lived refresh token in addition to the legitimate one.\n\n### Credit\nThis issue was reported by [@eddieran](https://github.com/eddieran).",
"id": "GHSA-8m7c-hf24-5g47",
"modified": "2026-07-20T21:18:55Z",
"published": "2026-06-05T16:20:32Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/nocodb/nocodb/security/advisories/GHSA-8m7c-hf24-5g47"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-47386"
},
{
"type": "PACKAGE",
"url": "https://github.com/nocodb/nocodb"
},
{
"type": "WEB",
"url": "https://github.com/nocodb/nocodb/releases/tag/2026.05.1"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "NocoDB: OAuth Authorization Code Race Condition"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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