CVE-2026-31875
Parse Server MFA recovery codes not consumed after use
Description
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.6.0 and 8.6.33, when multi-factor authentication (MFA) via TOTP is enabled for a user account, Parse Server generates two single-use recovery codes. These codes are intended as a fallback when the user cannot provide a TOTP token. However, recovery codes are not consumed after use, allowing the same recovery code to be used an unlimited number of times. This defeats the single-use design of recovery codes and weakens the security of MFA-protected accounts. An attacker who obtains a single recovery code can repeatedly authenticate as the affected user without the code ever being invalidated. This vulnerability is fixed in 9.6.0 and 8.6.33.
How to fix CVE-2026-31875
To remediate CVE-2026-31875, upgrade the affected package to a fixed version below.
- —upgrade to 8.6.33 or later
- —upgrade to 9.6.0-alpha.7 or later
Is CVE-2026-31875 being exploited?
Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 8.6.33, >= 9.0.0, < 9.6.0
- >= 9.0.0-alpha.1, < 9.6.0-alpha.7
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |