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4 vulnerabilities found for synapse by element
CVE-2026-45078 (GCVE-0-2026-45078)
Vulnerability from nvd – Published: 2026-05-28 15:52 – Updated: 2026-05-29 15:31
VLAI
Title
Synapse CPU starvation (Denial of Service)
Summary
Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, local authenticated users can cause Synapse to starve other requests of CPU and lead to other requests failing, causing other users to be denied service. This vulnerability is fixed in 1.152.1.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/element-hq/synapse/security/ad… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| element-hq | synapse |
Affected:
< 1.152.1
|
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CVE-2026-45076 (GCVE-0-2026-45076)
Vulnerability from nvd – Published: 2026-05-28 15:50 – Updated: 2026-06-02 14:51
VLAI
Title
Synapse pagination denial of service
Summary
Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, in federated rooms, malicious homeservers can craft room events in such a way that prevents Synapse from providing full history to paginating clients. Clients could therefore fail to display room history. This vulnerability is fixed in 1.152.1.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-20 - Improper Input Validation
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/element-hq/synapse/security/ad… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| element-hq | synapse |
Affected:
< 1.152.1
|
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CVE-2026-45078 (GCVE-0-2026-45078)
Vulnerability from cvelistv5 – Published: 2026-05-28 15:52 – Updated: 2026-05-29 15:31
VLAI
Title
Synapse CPU starvation (Denial of Service)
Summary
Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, local authenticated users can cause Synapse to starve other requests of CPU and lead to other requests failing, causing other users to be denied service. This vulnerability is fixed in 1.152.1.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/element-hq/synapse/security/ad… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| element-hq | synapse |
Affected:
< 1.152.1
|
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CVE-2026-45076 (GCVE-0-2026-45076)
Vulnerability from cvelistv5 – Published: 2026-05-28 15:50 – Updated: 2026-06-02 14:51
VLAI
Title
Synapse pagination denial of service
Summary
Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, in federated rooms, malicious homeservers can craft room events in such a way that prevents Synapse from providing full history to paginating clients. Clients could therefore fail to display room history. This vulnerability is fixed in 1.152.1.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-20 - Improper Input Validation
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/element-hq/synapse/security/ad… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| element-hq | synapse |
Affected:
< 1.152.1
|
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