CVE-2025-30355

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Source
https://cve.org/CVERecord?id=CVE-2025-30355
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-30355.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2025-30355
Aliases
Downstream
Related
Published
2025-03-27T00:59:27.996Z
Modified
2026-04-10T05:24:46.263978Z
Severity
  • 7.1 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H CVSS Calculator
Summary
Synapse vulnerable to federation denial of service via malformed events
Details

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.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/30xxx/CVE-2025-30355.json",
    "cwe_ids": [
        "CWE-20"
    ]
}
References

Affected packages

Git / github.com/element-hq/synapse

Affected ranges

Type
GIT
Repo
https://github.com/element-hq/synapse
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
2277df2a1eb685f85040ef98fa21d41aa4cdd389
Type
GIT
Repo
https://github.com/element-hq/synapse
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
ecc09b15f108a49348777c908af0187cf26d281e

Affected versions

Other
hhs-1
hhs-2
hhs-3
hhs-5
hhs-6
hhs-7
hhs-8
v0.*
v0.10.0
v0.10.0-r1
v0.10.0-r2
v0.11.0
v0.11.0-r1
v0.11.0-r2
v0.11.1
v0.12.0
v0.13.1
v0.13.2
v0.13.3
v0.14.0
v0.16.0
v0.16.1
v0.16.1-r1
v0.17.0
v0.17.1
v0.17.2
v0.17.3
v0.18.0
v0.18.1
v0.18.2
v0.18.3
v0.18.4
v0.18.5
v0.2.0
v0.2.1
v0.2.1a
v0.2.2
v0.23.0-rc1
v0.23.0-rc2
v0.25.0-rc1
v0.28.0-rc1
v0.3.0
v0.3.3
v0.3.4
v0.32.0
v0.32.0rc1
v0.32.2
v0.4.1
v0.4.2
v0.5.0
v0.5.1
v0.5.2
v0.5.3
v0.5.3a
v0.5.3b
v0.5.3c
v0.5.4
v0.5.4a
v0.6.0
v0.6.0a
v0.6.0b
v0.6.1
v0.6.1a
v0.6.1b
v0.6.1c
v0.6.1d
v0.6.1e
v0.6.1f
v0.7.0
v0.7.0a
v0.7.0b
v0.7.0c
v0.7.0d
v0.7.0e
v0.7.0f
v0.7.1
v0.7.1-r1
v0.7.1-r2
v0.7.1-r3
v0.7.1-r4
v0.8.0
v0.8.1
v0.8.1-r1
v0.8.1-r2
v0.8.1-r3
v0.8.1-r4
v0.9.0
v0.9.0-r1
v0.9.0-r2
v0.9.0-r3
v0.9.0-r4
v0.9.0-r5
v0.9.1
v0.9.2
v0.9.2-r1
v0.9.2-r2
v0.9.3
v0.99.1rc1
v0.99.2rc1
v0.99.4rc1
v0.99.5.1.dev0
v1.*
v1.1.0rc1
v1.1.0rc2
v1.10.0rc1
v1.100.0rc1
v1.100.0rc2
v1.100.0rc3
v1.101.0rc1
v1.103.0rc1
v1.104.0rc1
v1.105.0rc1
v1.106.0rc1
v1.11.0rc1
v1.111.0rc1
v1.112.0rc1
v1.114.0rc1
v1.115.0rc1
v1.116.0rc1
v1.12.0rc1
v1.121.0rc1
v1.123.0rc1
v1.124.0rc1
v1.126.0rc1
v1.126.0rc2
v1.126.0rc3
v1.127.0
v1.127.0rc1
v1.14.0rc1
v1.15.0rc1
v1.16.0rc1
v1.17.0rc1
v1.18.0rc1
v1.23.0rc1
v1.24.0rc1
v1.27.0rc1
v1.29.0rc1
v1.3.0rc1
v1.30.0rc1
v1.31.0rc1
v1.32.0rc1
v1.34.0rc1
v1.35.0rc1
v1.36.0rc1
v1.4.0rc1
v1.40.0rc1
v1.49.0rc1
v1.5.0rc1
v1.52.0rc1
v1.6.0rc1
v1.62.0rc1
v1.63.0rc1
v1.75.0rc1
v1.76.0rc1
v1.78.0rc1
v1.79.0rc1
v1.8.0rc1
v1.81.0rc1
v1.84.0rc1
v1.87.0rc1
v1.88.0rc1
v1.9.0.dev1
v1.9.0.dev2
v1.9.0rc1
v1.90.0rc1
v1.94.0rc1
v1.95.0rc1
v1.98.0rc1
v1.99.0rc1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-30355.json"