{"id":"CVE-2026-94450","aliases":["EUVD-2026-84822","GHSA-5rw2-6x5m-v22x"],"status":"published","title":"Potential denial of service when configured to send Retry packets in s2n-quic","description":"Improper validation of the Destination Connection ID length in s2n-quic 1.88.0 and earlier may allow an unauthenticated remote user to cause a denial of service by shutting down a server endpoint via a single crafted UDP datagram. Only server endpoints specifically configured to send Retry packets are affected.\n\n\n\nTo remediate this issue, users should upgrade to version v1.89.0 or later.","severity":{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.01944,"percentile":0.80325,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-1284","CWE-617"],"published":"2026-09-22T20:04:44Z","modified":"2026-10-28T02:30:24Z","products":[{"vendor":"aws","product":"s2n-quic"}],"references":[{"url":"https://github.com/aws/s2n-quic/releases/tag/v1.89.0","tags":["patch","release-notes","fix"]},{"url":"https://aws.amazon.com/security/security-bulletins/2026-116-aws/","tags":["vendor-advisory","advisory"]},{"url":"https://github.com/aws/s2n-quic/security/advisories/GHSA-5rw2-6x5m-v22x","tags":["release-notes","advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/94xxx/CVE-2026-94450.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-94450","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-94450","title":"Potential denial of service when configured to send Retry packets in s2n-quic","description":"Improper validation of the Destination Connection ID length in s2n-quic 1.88.0 and earlier may allow an unauthenticated remote user to cause a denial of service by shutting down a server endpoint via a single crafted UDP datagram. Only server endpoints specifically configured to send Retry packets are affected.\n\n\n\nTo remediate this issue, users should upgrade to version v1.89.0 or later.","status":"published","published":"2026-09-22T20:04:44.36Z","modified":"2026-10-20T18:11:41.209Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-1284","CWE-617"],"updated_at":"2026-11-02T14:19:54.122945Z"}],"euvd":[{"id":"EUVD-2026-84822","description":"Improper validation of the Destination Connection ID length in s2n-quic 1.88.0 and earlier may allow an unauthenticated remote user to cause a denial of service by shutting down a server endpoint via a single crafted UDP datagram. Only server endpoints specifically configured to send Retry packets are affected.\n\n\n\nTo remediate this issue, users should upgrade to version v1.89.0 or later.","status":"published","published":"2026-09-22T20:04:44Z","modified":"2026-10-20T18:11:41Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T16:59:43.145678Z"}],"nvd":[{"id":"CVE-2026-94450","description":"Improper validation of the Destination Connection ID length in s2n-quic 1.88.0 and earlier may allow an unauthenticated remote user to cause a denial of service by shutting down a server endpoint via a single crafted UDP datagram. Only server endpoints specifically configured to send Retry packets are affected.\n\n\n\nTo remediate this issue, users should upgrade to version v1.89.0 or later.","status":"published","published":"2026-09-22T21:17:33.867Z","modified":"2026-10-20T19:19:24.167Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-617","CWE-1284"],"updated_at":"2026-11-02T14:12:50.703874Z"}],"osv":[{"id":"CVE-2026-94450","title":"Potential denial of service when configured to send Retry packets in s2n-quic","description":"Improper validation of the Destination Connection ID length in s2n-quic 1.88.0 and earlier may allow an unauthenticated remote user to cause a denial of service by shutting down a server endpoint via a single crafted UDP datagram. Only server endpoints specifically configured to send Retry packets are affected.\n\n\n\nTo remediate this issue, users should upgrade to version v1.89.0 or later.","status":"published","published":"2026-09-22T20:04:44.36Z","modified":"2026-10-28T02:30:24.990503793Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-1284","CWE-617"],"updated_at":"2026-11-02T15:45:20.931171Z"}]}}