Summary
eduMFA: Incorrect InnoDB snapshot isolation possibly allows token reusage
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
- 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
- Same rules applies for Galera with underlying MariaDB
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/
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 versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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See it in your environmentNew to Kodem? Get a demo →Remediation advice
Fixed in version 2.9.1 by locking rows prior to write with SELECT FOR UPDATE.
Frequently Asked Questions
- What is GHSA-QQ2P-4282-CFC5? GHSA-QQ2P-4282-CFC5 is a high-severity security vulnerability in edumfa (pip), affecting versions < 2.9.1. It is fixed in 2.9.1.
- Which versions of edumfa are affected by GHSA-QQ2P-4282-CFC5? edumfa (pip) versions < 2.9.1 is affected.
- Is there a fix for GHSA-QQ2P-4282-CFC5? Yes. GHSA-QQ2P-4282-CFC5 is fixed in 2.9.1. Upgrade to this version or later.
- Is GHSA-QQ2P-4282-CFC5 exploitable, and should I be worried? Whether GHSA-QQ2P-4282-CFC5 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-QQ2P-4282-CFC5 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-QQ2P-4282-CFC5? Upgrade
edumfato 2.9.1 or later.