CVE-2023-41335: Temporary storage of plaintext passwords during password changes in matrix synapse
Impact
When users update their passwords, the new credentials may be briefly held in the server database. While this doesn't grant the server any added capabilities—it already learns the users' passwords as part of the authentication process—it does disrupt the expectation that passwords won't be stored in the database. As a result, these passwords could inadvertently be captured in database backups for a longer duration.
These temporarily stored passwords are automatically erased after a 48-hour window.
Patches https://github.com/matrix-org/synapse/pull/16272
References
This bug was due to a regression in https://github.com/matrix-org/synapse/pull/13188.
Other sources
Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. When users update their passwords, the new credentials may be briefly held in the server database. While this doesn't grant the server any added capabilities—it already learns the users' passwords as part of the authentication process—it does disrupt the expectation that passwords won't be stored in the database. As a result, these passwords could inadvertently be captured in database backups for a longer duration. These temporarily stored passwords are automatically erased after a 48-hour window. This issue has been addressed in version 1.93.0. Users are advised to upgrade. There are no known workarounds for this issue.
— MITRE
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is the impact of CVE-2023-41335?
When users update their passwords, the new credentials may be briefly held in the server database.
Does CVE-2023-41335 grant the server any added capabilities?
No, it does not grant the server any added capabilities.
What does CVE-2023-41335 disrupt?
CVE-2023-41335 disrupts the expectation that passwords won't be held in the server database.
How can I fix CVE-2023-41335?
To fix CVE-2023-41335, update your 'matrix-synapse' package to version 1.93.0 or higher.
Where can I find more information about CVE-2023-41335?
You can find more information about CVE-2023-41335 in the references: - [GitHub Advisory](https://github.com/matrix-org/synapse/security/advisories/GHSA-4f74-84v3-j9q5) - [GitHub Pull Request 1](https://github.com/matrix-org/synapse/pull/13188) - [GitHub Pull Request 2](https://github.com/matrix-org/synapse/pull/16272)