{"id":"CVE-2024-45397","url":"https://www.cyber-defence.io/tools/cve/CVE-2024-45397","generatedAt":"2026-10-28T04:02:33.777Z","title":"This behavior allows attackers on the network to execute HTTP requests from addresses that are otherwise rejected by the address-based access control.","description":"h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. When an HTTP request using TLS/1.3 early data on top of TCP Fast Open or QUIC 0-RTT packets is received and the IP-address-based access control is used, the access control does not detect and prohibit HTTP requests conveyed by packets with a spoofed source address. This behavior allows attackers on the network to execute HTTP requests from addresses that are otherwise rejected by the address-based access control. The vulnerability has been addressed in commit 15ed15a. Users may disable the use of TCP FastOpen and QUIC to mitigate the issue.","published":"2024-10-11T15:15:05.000Z","lastModified":"2026-06-17T07:54:08.000Z","status":"Analyzed","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"},"cwe":["CWE-284","CWE-290"],"affected":["dena/h2o"],"epss":{"score":0.00441,"percentile":0.38098,"date":"2026-10-27","history":[]},"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 (0.44%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/h2o/h2o/commit/15ed15a2efb83a77bb4baaa5a119e639c2f6898a","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/h2o/h2o/security/advisories/GHSA-jf2c-xjcp-wg4c","tags":["Vendor Advisory"],"source":"security-advisories@github.com"},{"url":"https://h2o.examp1e.net/configure/http3_directives.html","tags":["Product"],"source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2024-45397","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."}