CVE-2026-39321
published 2026-04-07CVE-2026-39321: 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…
PriorityP419low3.7CVSS 3.1
AVNACHPRNUINSUCLINAN
EPSS
0.23%
13.7th percentile
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.
Affected
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| parse-community | parse-server | < 8.6.74 | 8.6.74 |
| parse-community | parse-server | — | — |
| parse-community | parse-server | >= 0 < 8.6.74 | 8.6.74 |
| parse-community | parse-server | >= 9.0.0 < 9.8.0-alpha.6 | 9.8.0-alpha.6 |
| parseplatform | parse-server | < 8.6.74 | 8.6.74 |
| parseplatform | parse-server | — | — |
| parseplatform | parse-server | >= 9.0.0 < 9.8.0 | 9.8.0 |
CVSS provenance
nvdv3.13.7LOWCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
nvdv4.06.3MEDIUMCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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OSV
Parse Server has a login timing side-channel reveals user existence
osv·2026-04-08
CVE-2026-39321 [MEDIUM] Parse Server has a login timing side-channel reveals user existence
Parse Server has a login timing side-channel reveals user existence
### Impact
The 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.
### Patches
A dummy bcrypt comparison is now performed when no user is found, normalizing response timing regardless of user existence. Additionally, accounts without a stored password (e.g. OAuth-only) now also run a dummy comparison to prevent the same timing oracle.
### Workarounds
Configure rate limiting on the login endpoint t
GHSA
Parse Server has a login timing side-channel reveals user existence
ghsa·2026-04-08
CVE-2026-39321 [MEDIUM] CWE-208 Parse Server has a login timing side-channel reveals user existence
Parse Server has a login timing side-channel reveals user existence
### Impact
The 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.
### Patches
A dummy bcrypt comparison is now performed when no user is found, normalizing response timing regardless of user existence. Additionally, accounts without a stored password (e.g. OAuth-only) now also run a dummy comparison to prevent the same timing oracle.
### Workarounds
Configure rate limiting on the login endpoint t
No detection rules found.
No public exploits indexed.
2026-04-07
Published