{"id":"CVE-2026-14643","aliases":["GHSA-jr45-8vmc-qm54"],"url":"https://o3.security/vulnerability/CVE-2026-14643","summary":"undici vulnerable to cross-user information disclosure via whitespace around equals in Cache-Control directives","details":"## Impact\n\nUndici's cache interceptor mishandles optional whitespace (OWS) placed around the `=` of a qualified `no-cache` or `private` Cache-Control directive, such as `no-cache =\"authorization\"` (OWS before `=`) or `no-cache= \"authorization\"` (OWS after `=`). The parser either drops the directive entirely or stores a field name with literal quote characters, so the downstream cache decisions do not recognize the qualification and the response is stored.\n\nIn shared-cache mode, this allows a response containing one user's authenticated data to be served from cache to a subsequent caller, including an unauthenticated caller, when both requests resolve to the same cache key. The impact class is identical to CVE-2026-9678 (GHSA-pr7r-676h-xcf6); this advisory covers the whitespace-around-`=` bypass that the earlier fix did not normalize.\n\nAffected applications are those that explicitly enable the cache interceptor (`interceptors.cache()`) in shared mode, forward `Authorization` headers upstream, and receive cacheable responses with qualified `private` or `no-cache` directives whose field-name list is padded with OWS around the `=`.\n\n## Patches\n\nUpgrade to undici v7.29.0 or v8.9.0.\n\n## Workarounds\n\nIf upgrade is not immediately possible, disable shared-cache mode for traffic that includes `Authorization` headers, avoid caching responses to authenticated requests, or add `Vary: Authorization` upstream.","published":"2026-07-29T21:08:33.311Z","modified":"2026-10-28T02:30:39.045283867Z","cvss":{"score":5.9,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N"},"epss":{"score":0.00304,"percentile":0.23167,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"undici","fixedVersion":"7.29.0"},{"ecosystem":"npm","name":"undici","fixedVersion":"8.9.0"}],"fix":{"url":"https://github.com/nodejs/undici/commit/85a240551c9feb8b8a0ecc56c84b2b3015add8a9","label":"nodejs/undici@85a2405"},"references":[{"type":"ADVISORY","url":"https://cna.openjsf.org/security-advisories.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/14xxx/CVE-2026-14643.json"},{"type":"ADVISORY","url":"https://github.com/nodejs/undici/security/advisories/GHSA-jr45-8vmc-qm54"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-14643"},{"type":"WEB","url":"https://github.com/nodejs/undici/commit/85a240551c9feb8b8a0ecc56c84b2b3015add8a9"},{"type":"WEB","url":"https://github.com/nodejs/undici/commit/cb105d7c79069150982fa11acada0dd94a60dbbc"},{"type":"PACKAGE","url":"https://github.com/nodejs/undici"},{"type":"WEB","url":"https://github.com/nodejs/undici/releases/tag/v7.29.0"},{"type":"WEB","url":"https://github.com/nodejs/undici/releases/tag/v8.9.0"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:30:39.045283867Z"}}