CVE-2026-39321

Parse Server has a login timing side-channel reveals user existence

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

Weaknesses (CWE)

• CWE-208

Advisories

• GHSA-mmpq-5hcv-hf2v — Parse Server has a login timing side-channel reveals user existence

European references

• ENISA EUVD · EUVD-2026-19818
• GCVE · GCVE-0-2026-39321

Affected configurations (NVD CPE)

• cpe:2.3:a:parseplatform:parse-server:*:*:*:*:*:node.js:*:* < 8.6.74
• cpe:2.3:a:parseplatform:parse-server:*:*:*:*:*:node.js:*:* ≥ 9.0.0 < 9.8.0
• cpe:2.3:a:parseplatform:parse-server:9.8.0:alpha1:*:*:*:node.js:*:*
• cpe:2.3:a:parseplatform:parse-server:9.8.0:alpha2:*:*:*:node.js:*:*
• cpe:2.3:a:parseplatform:parse-server:9.8.0:alpha3:*:*:*:node.js:*:*
• cpe:2.3:a:parseplatform:parse-server:9.8.0:alpha4:*:*:*:node.js:*:*
• cpe:2.3:a:parseplatform:parse-server:9.8.0:alpha5:*:*:*:node.js:*:*

Affected products

References

• https://github.com/parse-community/parse-server/security/advisories/GHSA-mmpq-5hcv-hf2v
• https://github.com/parse-community/parse-server/pull/10398
• https://github.com/parse-community/parse-server/pull/10399

Sources