GHSA-qq2p-4282-cfc5
eduMFA: Incorrect InnoDB snapshot isolation possibly allows token reusage
Impact
For deployments using MySQL or MariaDB < 11.6.2 (or newer with innodb_snapshot_isolation=off) reusage of token values might be possible due to faulty transaction isolation inside the database. Exploiting this requires racing this transaction. Affected are all tokentypes whose values are only supposed to be used once, for example TOTP, HOTP and likely also WebAuthN.
Affected Combinations:
- MySQL (any version)
- MariaDB with innodb_snapshot_isolation=OFF
- innodb_snapshot_isolation was introduced in: MariaDB 10.6.18, MariaDB 10.11.8, MariaDB 11.0.6, MariaDB 11.1.5, MariaDB 11.2.4, MariaDB 11.4.2 with default OFF, can be turned ON as a workaround
- for MariaDB >= 11.6.2 the default is ON, which is not affected
- Same rules applies for Galera with underlying MariaDB
Patches
Fixed in version 2.9.1 by locking rows prior to write with SELECT FOR UPDATE.
Workarounds
Set innodb_snapshot_isolation to ON (default in MariaDB >= 11.6.2, e.g packaged in Debian 13).
Resources
https://mariadb.com/resources/blog/isolation-level-violation-testing-and-debugging-in-mariadb/
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- High
- Integrity
- Low
- Availability
- Low
What each source reports
GitHub Advisories Score used
eduMFA: Incorrect InnoDB snapshot isolation possibly allows token reusage
Impact
For deployments using MySQL or MariaDB < 11.6.2 (or newer with innodb_snapshot_isolation=off) reusage of token values might be possible due to faulty transaction isolation inside the database. Exploiting this requires racing this transaction. Affected are all tokentypes whose values are only supposed to be used once, for example TOTP, HOTP and likely also WebAuthN.
Affected Combinations:
- MySQL (any version)
- MariaDB with innodb_snapshot_isolation=OFF
- innodb_snapshot_isolation was introduced in: MariaDB 10.6.18, MariaDB 10.11.8, MariaDB 11.0.6, MariaDB 11.1.5, MariaDB 11.2.4, MariaDB 11.4.2 with default OFF, can be turned ON as a workaround
- for MariaDB >= 11.6.2 the default is ON, which is not affected
- Same rules applies for Galera with underlying MariaDB
Patches
Fixed in version 2.9.1 by locking rows prior to write with SELECT FOR UPDATE.
Workarounds
Set innodb_snapshot_isolation to ON (default in MariaDB >= 11.6.2, e.g packaged in Debian 13).
Resources
https://mariadb.com/resources/blog/isolation-level-violation-testing-and-debugging-in-mariadb/
- Record
GHSA-qq2p-4282-cfc5- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:H/VI:L/VA:L/SC:H/SI:L/SA:L - Weakness
- CWE-285
- Updated
- 2026-11-02
OSV
eduMFA: Incorrect InnoDB snapshot isolation possibly allows token reusage
Impact
For deployments using MySQL or MariaDB < 11.6.2 (or newer with innodb_snapshot_isolation=off) reusage of token values might be possible due to faulty transaction isolation inside the database. Exploiting this requires racing this transaction. Affected are all tokentypes whose values are only supposed to be used once, for example TOTP, HOTP and likely also WebAuthN.
Affected Combinations:
- MySQL (any version)
- MariaDB with innodb_snapshot_isolation=OFF
- innodb_snapshot_isolation was introduced in: MariaDB 10.6.18, MariaDB 10.11.8, MariaDB 11.0.6, MariaDB 11.1.5, MariaDB 11.2.4, MariaDB 11.4.2 with default OFF, can be turned ON as a workaround
- for MariaDB >= 11.6.2 the default is ON, which is not affected
- Same rules applies for Galera with underlying MariaDB
Patches
Fixed in version 2.9.1 by locking rows prior to write with SELECT FOR UPDATE.
Workarounds
Set innodb_snapshot_isolation to ON (default in MariaDB >= 11.6.2, e.g packaged in Debian 13).
Resources
https://mariadb.com/resources/blog/isolation-level-violation-testing-and-debugging-in-mariadb/
- Record
GHSA-qq2p-4282-cfc5- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:H/VI:L/VA:L/SC:H/SI:L/SA:L - Weakness
- CWE-285
- Updated
- 2026-11-02
Affected packages
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | GitHub Advisories, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
GHSA-qq2p-4282-cfc5 is a high vulnerability (CVSS 7.1) in edumfa, published May 18, 2026. No source lists public exploit code. Fixed in edumfa 2.9.1.