Synapse
Description
Synapse is an open source Matrix homeserver implementation, written and maintained by Element. Matrix is the open standard for secure and interoperable real time communications.
Product name
synapse
Related organization
CVE-2025-61672 (GCVE-0-2025-61672)
Vulnerability from – Published: 2025-10-08 14:55 – Updated: 2025-10-15 16:11
VLAI?
Summary
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 homeservers. The issue is patched in Synapse 1.138.3, 1.138.4, 1.139.1, and 1.139.2. Note that even though 1.138.3 and 1.139.1 fix the vulnerability, they inadvertently introduced an unrelated regression. For this reason, the maintainers of Synapse recommend skipping these releases and upgrading straight to 1.138.4 and 1.139.2.
Severity ?
CWE
- CWE-1287 - Improper Validation of Specified Type of Input
Assigner
References
| URL | Tags | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
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Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| element-hq | synapse |
Affected:
< 1.138.3
Affected: = 1.139.0 |
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CVE-2025-30355 (GCVE-0-2025-30355)
Vulnerability from – Published: 2025-03-27 00:59 – Updated: 2025-03-27 13:47
VLAI?
Summary
Synapse is an open source Matrix homeserver implementation. 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 and has been fixed in Synapse v1.127.1. No known workarounds are available.
Severity ?
7.1 (High)
CWE
- CWE-20 - Improper Input Validation
Assigner
References
| URL | Tags | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
|||||||||||
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| element-hq | synapse |
Affected:
< 1.127.1
|
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CVE-2024-31208 (GCVE-0-2024-31208)
Vulnerability from – Published: 2024-04-23 17:26 – Updated: 2025-02-13 17:47
VLAI?
Summary
Synapse is an open-source Matrix homeserver. A remote Matrix user with malicious intent, sharing a room with Synapse instances before 1.105.1, can dispatch specially crafted events to exploit a weakness in the V2 state resolution algorithm. This can induce high CPU consumption and accumulate excessive data in the database of such instances, resulting in a denial of service. Servers in private federations, or those that do not federate, are not affected. Server administrators should upgrade to 1.105.1 or later. Some workarounds are available. One can ban the malicious users or ACL block servers from the rooms and/or leave the room and purge the room using the admin API.
Severity ?
6.5 (Medium)
CWE
- CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| element-hq | synapse |
Affected:
< 1.105.1
|
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displaying 1 - 3 organizations in total 3