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
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-02 14:51 UTC
CWE
  • CWE-20 - Improper Input Validation
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7760 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
element-hq synapse Affected: < 1.152.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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