{"id":"CVE-2026-47675","aliases":["CLSA-2026-1790597695","EUVD-2026-32925","GHSA-26pp-8wgv-hjvm","GHSA-3hrh-pfw6-9m5x","ROOT-APP-NPM-CVE-2026-47675"],"status":"published","title":"Hono: Cookie helper does not sanitize sameSite and priority, allowing Set-Cookie injection","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.21, the serialize() function in hono/cookie validates domain and path options against characters that corrupt Set-Cookie header syntax (;, \\r, \\n), but does not apply the same validation to sameSite and priority. An application that passes user-controlled input into either option may produce a Set-Cookie response header containing attacker-chosen additional attributes. This vulnerability is fixed in 4.12.21.","severity":{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00216,"percentile":0.12111,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-113","CWE-1287"],"published":"2026-05-28T15:28:23Z","modified":"2026-10-28T02:31:06Z","fixes":[{"ecosystem":"npm","package":"hono","fixed_in":["4.12.21"],"sources":["ghsa","osv"]},{"ecosystem":"Root:npm","package":"@rootio/hono","fixed_in":["4.12.14-root.io.6","4.12.14-root.io.7","4.12.14-root.io.8","4.12.12-root.io.2"],"sources":["osv"]},{"ecosystem":"Root:npm","package":"hono","fixed_in":["4.12.14-aikido.6","4.12.14-aikido.7","4.12.14-aikido.8","4.12.12-aikido.2"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"hono","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.12.21"}]}]},{"source":"osv","ecosystem":"TuxCare:npm","package":"hono","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.12.12-tuxcare.0"},{"fixed":"3.12.12-tuxcare.2"}]}],"versions":["3.12.12","3.12.12-tuxcare.1"],"bundled":11},{"source":"osv","ecosystem":"npm","package":"hono","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"4.12.21"}]}]},{"source":"osv","ecosystem":"Root:npm","package":"@rootio/hono","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.12.14-root.io.6"},{"fixed":"4.12.14-root.io.7"},{"fixed":"4.12.14-root.io.8"},{"fixed":"4.12.12-root.io.2"}]}]},{"source":"osv","ecosystem":"Root:npm","package":"hono","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.12.14-aikido.6"},{"fixed":"4.12.14-aikido.7"},{"fixed":"4.12.14-aikido.8"},{"fixed":"4.12.12-aikido.2"}]}]}],"products":[{"vendor":"hono","product":"hono"},{"vendor":"honojs","product":"hono"}],"references":[{"url":"https://github.com/honojs/hono/security/advisories/GHSA-3hrh-pfw6-9m5x","tags":["x_refsource_CONFIRM","Vendor Advisory","advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-47675","tags":["advisory"]},{"url":"https://github.com/honojs/hono/commit/905aedbc20661e0e2fa378783a7ec44a5c3df43d","tags":["web"]},{"url":"https://github.com/honojs/hono/releases/tag/v4.12.21","tags":["web"]},{"url":"https://github.com/advisories/GHSA-3hrh-pfw6-9m5x"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/47xxx/CVE-2026-47675.json","tags":["advisory"]},{"url":"https://github.com/honojs/hono","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-47675","title":"Hono: Cookie helper does not sanitize sameSite and priority, allowing Set-Cookie injection","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.21, the serialize() function in hono/cookie validates domain and path options against characters that corrupt Set-Cookie header syntax (;, \\r, \\n), but does not apply the same validation to sameSite and priority. An application that passes user-controlled input into either option may produce a Set-Cookie response header containing attacker-chosen additional attributes. This vulnerability is fixed in 4.12.21.","status":"published","published":"2026-05-28T15:28:23.458Z","modified":"2026-05-28T19:17:17.728Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-113","CWE-1287"],"updated_at":"2026-11-02T13:36:40.478484Z"}],"euvd":[{"id":"EUVD-2026-32925","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.21, the serialize() function in hono/cookie validates domain and path options against characters that corrupt Set-Cookie header syntax (;, \\r, \\n), but does not apply the same validation to sameSite and priority. An application that passes user-controlled input into either option may produce a Set-Cookie response header containing attacker-chosen additional attributes. This vulnerability is fixed in 4.12.21.","status":"published","published":"2026-05-28T15:28:23Z","modified":"2026-05-28T19:17:17Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T18:21:01.680356Z"}],"ghsa":[{"id":"GHSA-3hrh-pfw6-9m5x","title":"Hono: Cookie helper does not sanitize sameSite and priority, allowing Set-Cookie injection","description":"### Summary\n\nThe `serialize()` function in `hono/cookie` validates `domain` and `path` options against characters that corrupt `Set-Cookie` header syntax (`;`, `\\r`, `\\n`), but does not apply the same validation to `sameSite` and `priority`. An application that passes user-controlled input into either option may produce a `Set-Cookie` response header containing attacker-chosen additional attributes.\n\n### Details\n\nWhen constructing a `Set-Cookie` header value, `serialize()` appends the `sameSite` and `priority` option values directly into the output string after a presentation-only transformation (capitalizing the first character). Although the TypeScript type signature constrains these options to specific string literals, that constraint is not enforced at runtime; any string value, including one containing `;` or line-feed characters, passes through unchanged.\n\nThe validation guard that rejects `;`, `\\r`, and `\\n` from `domain` and `path` is not applied to `sameSite` or `priority`. An application that passes a request-derived value to either option therefore provides an injection point into the header line.\n\nThis issue arises when an application passes user-controlled input to the `sameSite` or `priority` option of `setCookie()` or `serialize()`.\n\n### Impact\n\nAn attacker who can control the `sameSite` or `priority` option value may inject additional attributes into a `Set-Cookie` response header.\n\nThis may lead to:\n\n- Cookie attribute injection — overriding `Domain`, `Path`, `HttpOnly`, `Secure`, or `Max-Age` for the affected cookie\n- HTTP response header injection on runtimes that do not strictly validate header values, enabling a second attacker-controlled `Set-Cookie` header in the same response\n\nThis issue affects applications that pass user-derived input into the `sameSite` or `priority` option of `hono/cookie` serialization functions.","status":"published","published":"2026-06-04T17:59:25Z","modified":"2026-06-04T17:59:27Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-113","CWE-1287"],"updated_at":"2026-11-02T14:40:16.698699Z"}],"nvd":[{"id":"CVE-2026-47675","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.21, the serialize() function in hono/cookie validates domain and path options against characters that corrupt Set-Cookie header syntax (;, \\r, \\n), but does not apply the same validation to sameSite and priority. An application that passes user-controlled input into either option may produce a Set-Cookie response header containing attacker-chosen additional attributes. This vulnerability is fixed in 4.12.21.","status":"published","published":"2026-05-28T17:16:32.537Z","modified":"2026-10-14T20:10:00.19Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-113","CWE-1287"],"updated_at":"2026-11-02T14:12:21.244426Z"}],"osv":[{"id":"CVE-2026-47675","title":"Hono: Cookie helper does not sanitize sameSite and priority, allowing Set-Cookie injection","description":"Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.21, the serialize() function in hono/cookie validates domain and path options against characters that corrupt Set-Cookie header syntax (;, \\r, \\n), but does not apply the same validation to sameSite and priority. An application that passes user-controlled input into either option may produce a Set-Cookie response header containing attacker-chosen additional attributes. This vulnerability is fixed in 4.12.21.","status":"published","published":"2026-05-28T15:28:23.458Z","modified":"2026-10-28T02:31:06.62362964Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-113","CWE-1287"],"updated_at":"2026-11-02T15:45:06.231145Z"},{"id":"GHSA-3hrh-pfw6-9m5x","title":"Hono: Cookie helper does not sanitize sameSite and priority, allowing Set-Cookie injection","description":"### Summary\n\nThe `serialize()` function in `hono/cookie` validates `domain` and `path` options against characters that corrupt `Set-Cookie` header syntax (`;`, `\\r`, `\\n`), but does not apply the same validation to `sameSite` and `priority`. An application that passes user-controlled input into either option may produce a `Set-Cookie` response header containing attacker-chosen additional attributes.\n\n### Details\n\nWhen constructing a `Set-Cookie` header value, `serialize()` appends the `sameSite` and `priority` option values directly into the output string after a presentation-only transformation (capitalizing the first character). Although the TypeScript type signature constrains these options to specific string literals, that constraint is not enforced at runtime; any string value, including one containing `;` or line-feed characters, passes through unchanged.\n\nThe validation guard that rejects `;`, `\\r`, and `\\n` from `domain` and `path` is not applied to `sameSite` or `priority`. An application that passes a request-derived value to either option therefore provides an injection point into the header line.\n\nThis issue arises when an application passes user-controlled input to the `sameSite` or `priority` option of `setCookie()` or `serialize()`.\n\n### Impact\n\nAn attacker who can control the `sameSite` or `priority` option value may inject additional attributes into a `Set-Cookie` response header.\n\nThis may lead to:\n\n- Cookie attribute injection — overriding `Domain`, `Path`, `HttpOnly`, `Secure`, or `Max-Age` for the affected cookie\n- HTTP response header injection on runtimes that do not strictly validate header values, enabling a second attacker-controlled `Set-Cookie` header in the same response\n\nThis issue affects applications that pass user-derived input into the `sameSite` or `priority` option of `hono/cookie` serialization functions.","status":"published","published":"2026-06-04T17:59:25Z","modified":"2026-09-10T03:50:55.293982711Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-113","CWE-1287"],"updated_at":"2026-11-02T15:46:35.747385Z"},{"id":"CLSA-2026-1790597695","title":"TuxCare security update for hono (12 CVEs)","description":"TuxCare rebuilt hono to address 12 CVEs. Fixed in 3.12.12-tuxcare.2.","status":"published","published":"2026-09-28T12:14:55Z","modified":"2026-10-15T09:48:03.104113003Z","updated_at":"2026-11-02T15:43:48.65893Z"},{"id":"ROOT-APP-NPM-CVE-2026-47675","title":"CVE-2026-47675 in @rootio/hono - Patched by Root","description":"Root has patched CVE-2026-47675 in the @rootio/hono package for Root:npm. Multiple fixed versions available.","status":"published","published":"2026-07-27T08:20:49Z","modified":"2026-07-27T13:15:24.621823599Z","updated_at":"2026-11-02T15:53:27.649662Z"}]}}