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A change in ownership and what it means for our readers.

Cisco encourages users to update to an unaffected version of its Adaptive Security Appliance (ASA) software since there are no workarounds for the 2014 vulnerability.

Stanislav Moiseyev, the organizer of the notorious Hydra Market, has been sentenced to life imprisonment by a Moscow court. Learn about the massive scale of this dark web marketplace and the international efforts to dismantle it.

### Impact The Sliding Sync feature on Synapse versions between 1.113.0rc1 and 1.120.0 can leak partial room state changes to users no longer in a room. Non-state events, like messages, are unaffected. ### Patches Synapse version 1.120.1 fixes the problem. ### Workarounds Disable Sliding Sync. ### References https://github.com/matrix-org/matrix-spec-proposals/pull/4186 https://github.com/element-hq/synapse/blob/d80cd57c54427687afcb48740d99219c88a0fff1/synapse/config/experimental.py#L341-L344 ### For more information If you have any questions or comments about this advisory, please email us at [security at element.io](mailto:security@element.io).

### Impact Synapse versions before 1.120.1 fail to properly validate invites received over federation. This vulnerability allows a malicious server to send a specially crafted invite that disrupts the invited user's `/sync` functionality. ### Patches Synapse 1.120.1 rejects such invalid invites received over federation and restores the ability to sync for affected users. ### Workarounds Server administrators can disable federation from untrusted servers. ### For more information If you have any questions or comments about this advisory, please email us at [security at element.io](mailto:security@element.io).

### Impact In Synapse before 1.120.1, `multipart/form-data` requests can in certain configurations transiently increase memory consumption beyond expected levels while processing the request, which can be used to amplify denial of service attacks. ### Patches Synapse 1.120.1 resolves the issue by denying requests with unsupported `multipart/form-data` content type. ### Workarounds Limiting request sizes or blocking the `multipart/form-data` content type before the requests reach Synapse, for example in a reverse proxy, alleviates the issue. Another approach that mitigates the attack is to use a low `max_upload_size` in Synapse. ### References - https://github.com/twisted/twisted/issues/4688#issuecomment-1167705518 - https://github.com/twisted/twisted/issues/4688#issuecomment-2385711609 ### For more information If you have any questions or comments about this advisory, please email us at [security at element.io](mailto:security@element.io).

### 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 elem...

### Impact Synapse versions before 1.106 are vulnerable to a disk fill attack, where an unauthenticated adversary can induce Synapse to download and cache large amounts of remote media. The default rate limit strategy is insufficient to mitigate this. This can lead to a denial of service, ranging from further media uploads/downloads failing to completely unavailability of the Synapse process, depending on how Synapse was deployed. ### Patches Synapse 1.106 introduces a new "leaky bucket" rate limit on remote media downloads to reduce the amount of data a user can request at a time. This does not fully address the issue, but does limit an unauthenticated user's ability to request large amounts of data to be cached. ### Workarounds Synapse deployments can currently decrease the maximum file size allowed, as well as increase request rate limits. However, this does not as effectively address the issue as a dedicated rate limit on remote media downloads. Server operators may also wish...