2021-07-01 09:51 UTC (updated)

There is announcement about yesterday update on Matrix blog: https://matrix.org/blog/2021/06/30/security-update-synapse-1-37-1-released

Homeserver owners with open registration, review your users in synapse-admin, please

PS: I added RSS feed of matrix.org blog to this room, so you will see such updates as soon as they posted

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