{"cve":"CVE-2026-45078","nvd":{"published":"2026-05-28T17:16:31.750","modified":"2026-10-26T13:10:00.140","status":"Analyzed","description":"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.","cvss_v4":{"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":6.8},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-770"],"references":["https://github.com/element-hq/synapse/security/advisories/GHSA-8q93-326v-3m7g"],"products":["element:synapse"],"source":"nvd","synced_at":"2026-10-26T13:39:24.642594360+00:00"},"epss":{"cve":"CVE-2026-45078","score":0.00128,"percentile":0.02454,"date":"2026-10-26"},"kev":null,"osv":[{"id":"GHSA-8q93-326v-3m7g","url":"https://osv.dev/vulnerability/GHSA-8q93-326v-3m7g","summary":"Synapse CPU starvation (Denial of Service)","modified":"2026-09-10T03:51:04.962109818Z","packages":[{"ecosystem":"PyPI","name":"matrix-synapse","purl":"pkg:pypi/matrix-synapse","ranges":["<1.152.1"],"fixed":["1.152.1"]}]},{"id":"PYSEC-2026-191","url":"https://osv.dev/vulnerability/PYSEC-2026-191","summary":"","modified":"2026-06-03T12:45:18.070288002Z","packages":[{"ecosystem":"PyPI","name":"matrix-synapse","purl":"pkg:pypi/matrix-synapse","ranges":["<1.152.1"],"fixed":["1.152.1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}