{"id":"CVE-2023-6193","aliases":["GHSA-w3vp-jw9m-f9pm"],"url":"https://o3.security/vulnerability/CVE-2023-6193","summary":"Unbounded queuing of path validation messages in cloudflare-quiche","details":"### Impact\nquiche v. 0.15.0 through 0.19.0 was discovered to be vulnerable to unbounded queuing of path validation messages, which could lead to excessive resource consumption.\n\nQUIC path validation ([RFC 9000 Section 8.2](https://datatracker.ietf.org/doc/html/rfc9000#section-8.2)) requires that the recipient of a PATH_CHALLENGE frame responds by sending a PATH_RESPONSE. An unauthenticated remote attacker can exploit the vulnerability by sending PATH_CHALLENGE frames and manipulating the connection (e.g. by restricting the peer's congestion window size) so that PATH_RESPONSE frames can only be sent at the slower rate than they are received, leading to storage of path validation data in an unbounded queue.\n\n### Patches\nQuiche versions greater than 0.19.0 address this problem.\n\n### References\n[CVE-2023-6193](https://www.cve.org/CVERecord?id=CVE-2023-6193)\n[RFC 9000 Section 8.2](https://datatracker.ietf.org/doc/html/rfc9000#section-8.2)","published":"2023-12-12T13:32:03.183Z","modified":"2026-08-12T03:51:22.303452721Z","cvss":{"score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"quiche","fixedVersion":"0.19.1"}],"fix":{"url":"https://github.com/cloudflare/quiche/commit/ea7ecf39ae28ab24cf1785c1674dc2e8a076f9ca","label":"cloudflare/quiche@ea7ecf3"},"references":[{"type":"WEB","url":"https://datatracker.ietf.org/doc/html/rfc9000#section-8.2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/6xxx/CVE-2023-6193.json"},{"type":"ADVISORY","url":"https://github.com/cloudflare/quiche/security/advisories/GHSA-w3vp-jw9m-f9pm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-6193"},{"type":"WEB","url":"https://github.com/cloudflare/quiche/commit/ea7ecf39ae28ab24cf1785c1674dc2e8a076f9ca"},{"type":"PACKAGE","url":"https://github.com/cloudflare/quiche"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:22.303452721Z"}}