CVE-2023-41335

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.

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.

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.

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.

These are all security issues fixed in the matrix-synapse-1.93.0-1.1 package on the GA media of openSUSE Tumbleweed.

It was discovered that Synapse network policies could be bypassed via specially crafted URLs. An attacker could possibly use this issue to bypass authentication mechanisms. (CVE-2023-32683)

It was discovered that Synapse exposed cached device information. An attacker could possibly use this issue to gain access to sensitive information. (CVE-2023-43796)

It was discovered that Synapse could be tricked into rejecting state changes in rooms. An attacker could possibly use this issue to cause Synapse to stop functioning properly, resulting in a denial of service. This issue was only fixed in Ubuntu 20.04 LTS and Ubuntu 22.04 LTS. (CVE-2022-39374)

It was discovered that Synapse stored user credentials in a server's database temporarily. An attacker could possibly use this issue to gain access to sensitive information. This issue was only fixed in Ubuntu 22.04 LTS. (CVE-2023-41335)

It was discovered that Synapse could incorrectly respond to server authorization events. An attacker could possibly use this issue to bypass authentication mechanisms. This issue was only fixed in Ubuntu 22.04 LTS. (CVE-2022-39335)

It was discovered that Synapse could be manipulated to mark messages as read when they had not been viewed. An attacker could possibly use this issue to perform repudiation-based attacks. This issue was only fixed in Ubuntu 22.04 LTS. (CVE-2023-42453)

It was discovered that Synapse had several memory-related issues. An attacker could possibly use this issue to cause Synapse to crash, resulting in a denial of service. This issue was only fixed in Ubuntu 22.04 LTS. (CVE-2024-31208)

It was discovered that Synapse could run external tools due to a unchecked thumbnail rendering routine. An attacker could possibly use this issue to cause Synapse to crash, resulting in a denial of service, or execute arbitrary code. This issue was only fixed in Ubuntu 22.04 LTS. (CVE-2024-53863)