### Impact Synapse before version 1.106 allows, by design, unauthenticated remote participants to trigger a download and caching of remote media from a remote homeserver to the local media repository. Such content then also becomes available for download from the local homeserver in an unauthenticated way. The implication is that unauthenticated remote adversaries can use this functionality to plant problematic content into the media repository. ### Patches Synapse 1.106 introduces a partial mitigation in the form of new endpoints which require authentication for media downloads. The unauthenticated endpoints will be frozen in a future release, closing the attack vector. ### Workarounds Though extremely limited, server operators can use more strict rate limits based on IP address. ### References * https://github.com/matrix-org/matrix-spec-proposals/pull/3916 ### For more information If you have any questions or comments about this advisory, please email us at [security at element.io](mailto:[email protected]).
Update matrix-synapse to 1.106 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanSynapse's unauthenticated writes to the media repository allow planting of problematic content affects matrix-synapse (pip). Severity is medium. ### Impact Synapse before version 1.106 allows, by design, unauthenticated remote participants to trigger a download and caching of remote media from a remote homeserver to the local media repository. Such content then also becomes available for download from the local homeserver in an unauthenticated way. The implication is that unauthenticated remote adversaries can use this functionality to plant problematic content into the media repository. ### Patches Synapse 1.106 introduces a partial mitigation in the form of new endpoints which require authentication for media downloads. The unauthenticated endpoints will be frozen in a future release, closing the attack vector. ### Workarounds Though extremely limited, server operators can use more strict rate limits based on IP address. ### References * https://github.com/matrix-org/matrix-spec-proposals/pull/3916 ### For more information If you have any questions or comments about this advisory, please email us at [security at element.io](mailto:[email protected]).
AI coding agents often install or upgrade packages automatically in pip. A medium vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
### Impact Synapse before version 1.106 allows, by design, unauthenticated remote participants to trigger a download and caching of remote media from a remote homeserver to the local media repository. Such content then also becomes available for download from the local homeserver in an unauthenticated way. The implication is that unauthenticated remote adversaries can use this functionality to plant problematic content into the media repository. ### Patches Synapse 1.106 introduces a partial mitigation in the form of new endpoints which require authentication for media downloads. The unauthenticated endpoints will be frozen in a future release, closing the attack vector. ### Workarounds Though extremely limited, server operators can use more strict rate limits based on IP address. ### References * https://github.com/matrix-org/matrix-spec-proposals/pull/3916 ### For more information If you have any questions or comments about this advisory, please email us at [security at element.io](mailto:[email protected]).
Update matrix-synapse to 1.106 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scanSynapse's unauthenticated writes to the media repository allow planting of problematic content affects matrix-synapse (pip). Severity is medium. ### Impact Synapse before version 1.106 allows, by design, unauthenticated remote participants to trigger a download and caching of remote media from a remote homeserver to the local media repository. Such content then also becomes available for download from the local homeserver in an unauthenticated way. The implication is that unauthenticated remote adversaries can use this functionality to plant problematic content into the media repository. ### Patches Synapse 1.106 introduces a partial mitigation in the form of new endpoints which require authentication for media downloads. The unauthenticated endpoints will be frozen in a future release, closing the attack vector. ### Workarounds Though extremely limited, server operators can use more strict rate limits based on IP address. ### References * https://github.com/matrix-org/matrix-spec-proposals/pull/3916 ### For more information If you have any questions or comments about this advisory, please email us at [security at element.io](mailto:[email protected]).
AI coding agents often install or upgrade packages automatically in pip. A medium vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|
| matrix-synapsepip | <1.106 | 1.106 |
|---|
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard| Package | Affected range | Fixed version |
|---|
| matrix-synapsepip | <1.106 | 1.106 |
|---|
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by GitHub Security Advisories (ghsa).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard