{"schema_version":"1.7.5","id":"GHSA-pr7r-676h-xcf6","published":"2026-06-18T14:28:13Z","modified":"2026-06-19T19:59:16.087921387Z","aliases":["CVE-2026-9678"],"related":["CGA-998f-mfgr-v7c9"],"summary":"undici vulnerable to cross-user information disclosure via shared cache whitespace bypass","details":"## Impact\n\nUndici's cache interceptor incorrectly classifies some responses as cacheable when the upstream `Cache-Control` header uses whitespace-padded qualified `private` or `no-cache` field names such as `private=\" authorization\"` or `no-cache=\"\\tauthorization\"`. The parser preserves the surrounding whitespace, so later comparisons against the literal `authorization` field name fail 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.\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 non-canonical qualified `private` or `no-cache` directives.\n\n## Patches\n\nUpgrade to undici v7.28.0 or v8.5.0.\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.","affected":[{"package":{"name":"undici","ecosystem":"npm","purl":"pkg:npm/undici"},"ranges":[{"type":"SEMVER","events":[{"introduced":"7.0.0"},{"fixed":"7.28.0"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-pr7r-676h-xcf6/GHSA-pr7r-676h-xcf6.json"}},{"package":{"name":"undici","ecosystem":"npm","purl":"pkg:npm/undici"},"ranges":[{"type":"SEMVER","events":[{"introduced":"8.0.0"},{"fixed":"8.5.0"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-pr7r-676h-xcf6/GHSA-pr7r-676h-xcf6.json"}}],"references":[{"type":"WEB","url":"https://github.com/nodejs/undici/security/advisories/GHSA-pr7r-676h-xcf6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-9678"},{"type":"WEB","url":"https://cna.openjsf.org/security-advisories.html"},{"type":"PACKAGE","url":"https://github.com/nodejs/undici"}],"database_specific":{"cwe_ids":["CWE-524"],"github_reviewed":true,"github_reviewed_at":"2026-06-18T14:28:13Z","nvd_published_at":"2026-06-17T18:18:06Z","severity":"MODERATE"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N"}]}