CVE-2026-39321
Parse Server has a login timing side-channel reveals user existence
- State
- Published
- Severity
- 6.3 Medium
- Published
- Apr 7, 2026
- Updated
- Apr 7, 2026
- Reserved
- Apr 6, 2026
Description
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.8.0-alpha.6 and 8.6.74, he login endpoint response time differs measurably depending on whether the submitted username or email exists in the database. When a user is not found, the server responds immediately. When a user exists but the password is wrong, a bcrypt comparison runs first, adding significant latency. This timing difference allows an unauthenticated attacker to enumerate valid usernames. This vulnerability is fixed in 9.8.0-alpha.6 and 8.6.74.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.3 Medium | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N | GitHub_M |
Weaknesses
- CWE-208 Observable Timing Discrepancy
Affected Products
| Product | Versions |
|---|---|
parse-serverparse-community |
|
References
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