{"id":"CVE-2026-103415","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-103415","generatedAt":"2026-10-28T03:41:57.940Z","title":"Both the length and the contents of that cookie come from the peer, and the write happens before certificate authentication completes, so a malicious or compromised server can overwrite memory past the caller supplied TLS packet buffer without…","description":"When a TLS 1.3 client processes a HelloRetryRequest, it copies the server's cookie into its second ClientHello without checking that the cookie fits in the outgoing packet. Both the length and the contents of that cookie come from the peer, and the write happens before certificate authentication completes, so a malicious or compromised server can overwrite memory past the caller supplied TLS packet buffer without presenting a certificate.\n\n\n\nOnly the client path is affected.","published":"2026-10-14T18:17:20.000Z","lastModified":"2026-10-16T21:17:13.000Z","status":"Awaiting Analysis","sourceIdentifier":"emo@eclipse.org","cvss":{"version":"4.0","score":9.3,"severity":"CRITICAL","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/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/M"},"cwe":["CWE-787"],"affected":[],"epss":{"score":0.00284,"percentile":0.20798,"date":"2026-10-27","history":[{"date":"2026-10-15","score":0.00284,"percentile":0.1951}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.28%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-14T18:17:20.000Z","detail":{"score":"9.3","severity":"CRITICAL","publishedAt":"2026-10-14T18:17:19.790Z"},"summary":"New CVE, critical severity (CVSS 9.3)."}],"references":[{"url":"https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-5pv3-rhf5-gwgq","source":"emo@eclipse.org"},{"url":"https://gitlab.eclipse.org/security/cve-assignment/-/work_items/357","source":"emo@eclipse.org"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-103415","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}