A malicious server can craft events which, when received, prevent Synapse version up to 1.127.0 from federating with other servers. The vulnerability has been exploited in the wild. Patches Fixed in Synapse v1.127.1. Workarounds Closed federation environments of trusted servers or non-federating installations are not affected.
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=df3e9a2457545ad613f6e3d1ce46f162d5631556 commit df3e9a2457545ad613f6e3d1ce46f162d5631556 Author: Petr Vaněk <arkamar@gentoo.org> AuthorDate: 2025-03-27 07:23:02 +0000 Commit: Petr Vaněk <arkamar@gentoo.org> CommitDate: 2025-03-27 08:12:02 +0000 net-im/synapse: add 1.127.1, CVE-2025-30355 Fixes an issue where a malicious server can craft events which, when received, prevent Synapse version up to 1.127.0 from federating with other servers. The vulnerability has been exploited in the wild. CVE: https://www.cve.org/CVERecord?id=CVE-2025-30355 GHSA: https://github.com/element-hq/synapse/security/advisories/GHSA-v56r-hwv5-mxg6 Bug: https://bugs.gentoo.org/952122 Signed-off-by: Petr Vaněk <arkamar@gentoo.org> net-im/synapse/Manifest | 1 + net-im/synapse/synapse-1.127.1.ebuild | 242 ++++++++++++++++++++++++++++++++++ 2 files changed, 243 insertions(+)
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=288171eb5e640b0fc61edad972fe94f6530d5e78 commit 288171eb5e640b0fc61edad972fe94f6530d5e78 Author: Petr Vaněk <arkamar@gentoo.org> AuthorDate: 2025-03-29 13:30:02 +0000 Commit: Petr Vaněk <arkamar@gentoo.org> CommitDate: 2025-03-29 13:30:02 +0000 net-im/synapse: drop 1.124.0, 1.125.0, 1.126.0, 1.127.0 Bug: https://bugs.gentoo.org/952122 Signed-off-by: Petr Vaněk <arkamar@gentoo.org> net-im/synapse/Manifest | 30 ----- net-im/synapse/synapse-1.124.0.ebuild | 229 -------------------------------- net-im/synapse/synapse-1.125.0.ebuild | 242 ---------------------------------- net-im/synapse/synapse-1.126.0.ebuild | 242 ---------------------------------- net-im/synapse/synapse-1.127.0.ebuild | 242 ---------------------------------- 5 files changed, 985 deletions(-)