CVE-2025-61672

CVE-2025-61672 affects the Synapse Matrix homeserver. The issue is caused by lack of validation for device keys in Synapse before 1.138.3 and in 1.139.0, enabling an attacker registered on the victim homeserver to degrade federation functionality and unpredictably break outbound federation to oth...

CVE-2025-61672: Improper Validation of Specified Type of Input

Synapse is an open source Matrix homeserver implementation. Lack of validation for device keys in Synapse before 1.138.3 and in Synapse 1.139.0 allow an attacker registered on the victim homeserver to degrade federation functionality, unpredictably breaking outbound federation to other homeserver...