{"id":"CVE-2026-39371","aliases":["GHSA-x8rx-789c-2pxq"],"url":"https://o3.security/vulnerability/CVE-2026-39371","summary":"RedwoodSDK has a CSRF vulnerability in server function dispatch via GET requests","details":"**Summary**\n\nServer functions exported from `\"use server\"` files could be invoked via GET requests, bypassing their intended HTTP method. In cookie-authenticated applications, this allowed cross-site GET navigations to trigger state-changing functions, because browsers send `SameSite=Lax` cookies on top-level GET requests.\n\nThis affected all server functions -- both `serverAction()` handlers and bare exported functions in `\"use server\"` files.\n\n**Impact**\n\nAn attacker could construct a URL containing a known action ID and JSON-encoded arguments. When a victim with an active session visited or was redirected to this URL, the function executed with the victim's credentials. This affected any server function that performs state-changing operations (writes, deletes, mutations) in applications using cookie-based authentication.\n\n**Remediation**\n\nUpdate to rwsdk `1.0.6`. No application code changes are required.\n\nThe fix enforces the declared HTTP method at dispatch time. GET requests to server functions that require POST now return `405 Method Not Allowed`.","published":"2026-04-07T19:28:30.941Z","modified":"2026-08-12T03:51:34.517942535Z","cvss":{"score":8.1,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H"},"epss":{"score":0.0021,"percentile":0.11503,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"rwsdk","fixedVersion":"1.0.6"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39371.json"},{"type":"ADVISORY","url":"https://github.com/redwoodjs/sdk/security/advisories/GHSA-x8rx-789c-2pxq"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-39371"},{"type":"PACKAGE","url":"https://github.com/redwoodjs/sdk"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:34.517942535Z"}}