PYSEC-2026-191

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Import Source
https://github.com/pypa/advisory-database/blob/main/vulns/matrix-synapse/PYSEC-2026-191.yaml
JSON Data
https://api.osv.dev/v1/vulns/PYSEC-2026-191
Aliases
Published
2026-05-28T17:16:31.750Z
Modified
2026-06-03T12:45:18.070288002Z
Severity
  • 5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

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.

References

Affected packages

PyPI / matrix-synapse

Package

Name
matrix-synapse
View open source insights on deps.dev
Purl
pkg:pypi/matrix-synapse

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.152.1

Affected versions

0.*
0.33.5
0.33.5.1
0.33.6rc1
0.33.6
0.33.7rc1
0.33.7rc2
0.33.7
0.33.8rc2
0.33.8
0.33.9
0.34.0rc1
0.34.0rc2
0.34.0
0.34.0.1
0.34.1.1
0.99.0rc1
0.99.0rc2
0.99.0rc3
0.99.0rc4
0.99.0
0.99.1rc1
0.99.1rc2
0.99.1
0.99.1.1
0.99.2rc1
0.99.2
0.99.3rc1
0.99.3
0.99.3.1
0.99.3.2
0.99.4rc1
0.99.4
0.99.5rc1
0.99.5
0.99.5.1
0.99.5.2
1.*
1.0.0rc1
1.0.0rc2
1.0.0rc3
1.0.0
1.1.0rc1
1.1.0rc2
1.1.0
1.2.0rc1
1.2.0rc2
1.2.0
1.2.1
1.3.0rc1
1.3.0
1.3.1
1.4.0rc1
1.4.0rc2
1.4.0
1.4.1rc1
1.4.1
1.5.0rc1
1.5.0rc2
1.5.0
1.5.1
1.6.0rc1
1.6.0rc2
1.6.0
1.6.1
1.7.0rc1
1.7.0rc2
1.7.0
1.7.1
1.7.2
1.7.3
1.8.0rc1
1.8.0
1.9.0.dev1
1.9.0.dev2
1.9.0rc1
1.9.0
1.9.1
1.10.0rc1
1.10.0rc2
1.10.0rc3
1.10.0rc5
1.10.0
1.10.1
1.11.0rc1
1.11.0
1.11.1
1.12.0rc1
1.12.0
1.12.1rc1
1.12.1
1.12.2
1.12.3
1.12.4rc1
1.12.4
1.13.0rc1
1.13.0rc2
1.13.0rc3
1.13.0
1.14.0rc1
1.14.0rc2
1.14.0
1.15.0rc1
1.15.0
1.15.1
1.15.2
1.16.0rc1
1.16.0rc2
1.16.0
1.16.1
1.17.0rc1
1.17.0
1.18.0rc1
1.18.0rc2
1.18.0
1.19.0rc1
1.19.0
1.19.1rc1
1.19.1
1.19.2
1.19.3
1.20.0rc1
1.20.0rc2
1.20.0rc3
1.20.0rc4
1.20.0rc5
1.20.0
1.20.1
1.21.0rc1
1.21.0rc2
1.21.0rc3
1.21.0
1.21.1
1.21.2
1.22.0rc1
1.22.0rc2
1.22.0
1.22.1
1.23.0rc1
1.23.0
1.23.1
1.24.0rc1
1.24.0rc2
1.24.0
1.25.0rc1
1.25.0
1.26.0rc1
1.26.0rc2
1.26.0
1.27.0rc1
1.27.0rc2
1.27.0
1.28.0rc1
1.28.0
1.29.0rc1
1.29.0
1.30.0rc1
1.30.0
1.30.1
1.31.0rc1
1.31.0
1.32.0rc1
1.32.0
1.32.1
1.32.2
1.33.0rc1
1.33.0rc2
1.33.0
1.33.1
1.33.2
1.34.0rc1
1.34.0
1.35.0rc1
1.35.0rc2
1.35.0rc3
1.35.0
1.35.1
1.36.0rc1
1.36.0rc2
1.36.0
1.37.0rc1
1.37.0
1.37.1rc1
1.37.1
1.38.0rc1
1.38.0rc2
1.38.0rc3
1.38.0
1.38.1
1.39.0rc1
1.39.0rc2
1.39.0rc3
1.39.0
1.40.0rc1
1.40.0rc2
1.40.0rc3
1.40.0
1.41.0rc1
1.41.0
1.41.1
1.42.0rc1
1.42.0rc2
1.42.0
1.43.0rc1
1.43.0rc2
1.43.0
1.44.0rc1
1.44.0rc2
1.44.0rc3
1.44.0
1.45.0rc1
1.45.0rc2
1.45.0
1.45.1
1.46.0rc1
1.46.0
1.47.0rc1
1.47.0rc2
1.47.0rc3
1.47.0
1.47.1
1.48.0rc1
1.48.0
1.49.0rc1
1.49.0
1.49.2
1.50.0rc1
1.50.0rc2
1.50.0
1.50.1
1.50.2
1.51.0rc1
1.51.0rc2
1.51.0
1.52.0rc1
1.52.0
1.53.0rc1
1.53.0
1.54.0rc1
1.54.0
1.55.0rc1
1.55.0
1.55.1
1.55.2
1.56.0rc1
1.56.0
1.57.0rc1
1.57.0
1.57.1
1.58.0rc2
1.58.0
1.58.1
1.59.0rc1
1.59.0rc2
1.59.0
1.59.1
1.60.0rc1
1.60.0rc2
1.60.0
1.61.0rc1
1.61.0
1.61.1
1.62.0rc1
1.62.0rc2
1.62.0rc3
1.62.0
1.63.0rc1
1.63.0
1.63.1
1.64.0rc1
1.64.0rc2
1.64.0
1.65.0rc1
1.65.0rc2
1.65.0
1.66.0rc1
1.66.0rc2
1.66.0
1.67.0rc1
1.67.0
1.68.0rc1
1.68.0rc2
1.68.0
1.69.0rc1
1.69.0rc2
1.69.0rc4
1.69.0
1.70.0rc1
1.70.0rc2
1.70.0
1.70.1
1.71.0rc1
1.71.0rc2
1.71.0
1.72.0rc1
1.72.0
1.73.0rc2
1.73.0
1.74.0rc1
1.74.0
1.75.0rc1
1.75.0rc2
1.75.0
1.76.0rc1
1.76.0rc2
1.76.0
1.77.0rc1
1.77.0rc2
1.77.0
1.78.0rc1
1.78.0
1.79.0rc1
1.79.0rc2
1.79.0
1.80.0rc1
1.80.0rc2
1.80.0
1.81.0rc1
1.81.0rc2
1.81.0
1.82.0rc1
1.82.0
1.83.0rc1
1.83.0
1.84.0rc1
1.84.0
1.84.1
1.85.0rc1
1.85.0rc2
1.85.0
1.85.1
1.85.2
1.86.0rc2
1.86.0
1.87.0rc1
1.87.0
1.88.0rc1
1.88.0
1.89.0rc1
1.89.0
1.90.0rc1
1.90.0
1.91.0rc1
1.91.0
1.91.1
1.91.2
1.92.0rc1
1.92.1
1.92.2
1.92.3
1.93.0rc1
1.93.0
1.94.0rc1
1.94.0
1.95.0rc1
1.95.0
1.95.1
1.96.0rc1
1.96.1
1.97.0rc1
1.97.0
1.98.0rc1
1.98.0
1.99.0rc1
1.99.0
1.100.0rc2
1.100.0rc3
1.100.0
1.101.0rc1
1.101.0
1.102.0rc1
1.102.0
1.103.0rc1
1.103.0
1.104.0rc1
1.104.0
1.105.0rc1
1.105.0
1.105.1
1.106.0rc1
1.106.0
1.107.0rc1
1.107.0
1.108.0rc1
1.108.0
1.109.0rc1
1.109.0rc2
1.109.0rc3
1.109.0
1.110.0rc2
1.110.0rc3
1.110.0
1.111.0rc1
1.111.0rc2
1.111.0
1.111.1
1.112.0rc1
1.112.0
1.113.0rc1
1.113.0
1.114.0rc1
1.114.0rc3
1.114.0
1.115.0rc1
1.115.0rc2
1.115.0
1.116.0rc1
1.116.0rc2
1.116.0
1.117.0rc1
1.117.0
1.118.0rc1
1.118.0
1.119.0rc2
1.119.0
1.120.0rc1
1.120.0
1.120.2
1.121.0rc1
1.121.0
1.121.1
1.122.0rc1
1.122.0
1.123.0rc1
1.123.0
1.124.0rc1
1.124.0rc2
1.124.0rc3
1.124.0
1.125.0rc1
1.125.0
1.126.0rc2
1.126.0rc3
1.126.0
1.127.0rc1
1.127.0
1.127.1
1.128.0rc1
1.128.0
1.129.0rc2
1.129.0
1.130.0rc1
1.130.0
1.131.0rc1
1.131.0
1.132.0rc1
1.132.0
1.133.0rc1
1.133.0
1.134.0rc1
1.134.0
1.135.0rc1
1.135.0rc2
1.135.0
1.135.2
1.136.0rc1
1.136.0rc2
1.136.0
1.137.0rc1
1.137.0
1.138.0rc1
1.138.0
1.138.2
1.138.3
1.138.4
1.139.0rc2
1.139.0rc3
1.139.0
1.139.1
1.139.2
1.140.0rc1
1.140.0
1.141.0rc1
1.141.0rc2
1.141.0
1.142.0rc3
1.142.0rc4
1.142.0
1.142.1
1.143.0rc2
1.143.0
1.144.0rc1
1.144.0
1.145.0rc1
1.145.0rc2
1.145.0rc3
1.145.0rc4
1.145.0
1.146.0rc1
1.146.0
1.147.0rc1
1.147.0
1.147.1
1.148.0rc1
1.148.0
1.149.0rc1
1.149.0
1.149.1
1.150.0rc1
1.150.0
1.151.0rc1
1.151.0
1.152.0rc1
1.152.0

Database specific

source 
"https://github.com/pypa/advisory-database/blob/main/vulns/matrix-synapse/PYSEC-2026-191.yaml"