Time-of-check Time-of-use (TOCTOU) Race Condition Affecting parse-server package, versions <8.6.64>=9.0.0 <9.7.0-alpha.8
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published29 Mar 2026
- disclosed29 Mar 2026
- creditoffset
Introduced: 29 Mar 2026
CVE-2026-34224 (opens in a new tab)How to fix?
Upgrade parse-server to version 8.6.64, 9.7.0-alpha.8 or higher.
Overview
parse-server is a version of the Parse backend that can be deployed to any infrastructure that can run Node.js.
Affected versions of this package are vulnerable to Time-of-check Time-of-use (TOCTOU) Race Condition through the authData login process. An attacker can maintain multiple authenticated sessions by sending concurrent login requests with a valid authentication provider token and a single MFA recovery code or SMS one-time password, thereby bypassing the intended single-use restriction and persisting sessions even after legitimate session revocation.