RedwoodSDK: Same-site CSRF in in server actions

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

RedwoodSDK is a server-first React framework. From version 1.0.0-beta.50 to before version 1.2.3, server actions in rwsdk apply HTTP method enforcement but no origin validation. A request originating from a different origin that the browser treats as same-site can invoke a server action with the victim's session cookie attached. This issue has been patched in version 1.2.3.

Source published

8 May 2026 19:35:17 UTC

Source modified

12 May 2026 18:32:06 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 3.1 · 5.3 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N

RedwoodSDK is a server-first React framework. From version 1.0.0-beta.50 to before version 1.2.3, server actions in rwsdk apply HTTP method enforcement but no origin validation. A request originating from a different origin that the browser treats as same-site can invoke a server action with the victim's session cookie attached. This issue has been patched in version 1.2.3.

Source published

May 8, 2026, 7:35:17 PM (timezone not stated)

Source modified

May 12, 2026, 6:32:06 PM (timezone not stated)

Observed here

7 Nov 2026 09:32:23 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 5.3 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N

RedwoodSDK is a server-first React framework. From version 1.0.0-beta.50 to before version 1.2.3, server actions in rwsdk apply HTTP method enforcement but no origin validation. A request originating from a different origin that the browser treats as same-site can invoke a server action with the victim's session cookie attached. This issue has been patched in version 1.2.3.

Source published

8 May 2026 20:16:31 UTC

Source modified

26 Oct 2026 00:10:00 UTC

Observed here

27 Oct 2026 11:12:01 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 5.3 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N

### Summary Server actions in `rwsdk` apply HTTP method enforcement but no origin validation. A request originating from a different origin that the browser treats as same-site can invoke a server action with the victim's session cookie attached. ### Impact An attacker who controls any origin the browser considers same-site with the deployed app can induce an authenticated victim's browser to invoke arbitrary server actions. The exposure depends on deployment shape: - Apps deployed on custom domains (for example `app.example.com`) are exposed whenever the attacker controls any sibling subdomain under the same registrable domain. Plausible vectors include subdomain takeover of stale DNS records pointing at third-party services, cross-site scripting on a sibling application, or content served from a user-content subdomain. - Apps deployed on platform-suffix domains on the Public Suffix List (`*.workers.dev`, `*.pages.dev`) are not exposed to the sibling-subdomain vector, because sibling subdomains under those suffixes are treated as cross-site. - In local development, `localhost` on any other port is treated as same-site with the app's dev server. A separate process running on the developer's machine can invoke server actions against the dev server. The attacker cannot read action responses (`mode: "no-cors"` yields opaque responses). Impact is therefore limited to side effects of action invocation: writes, state changes, and any externally observable action the application performs in response. Cross-site requests from unrelated origins (`evil.com` targeting `app.com`) are not affected because `SameSite=Lax` session cookies are not attached by default in that scenario. ### Affected Configurations Applications using `rwsdk` server actions (`serverAction()` or functions invoked via the RSC action protocol) in combination with cookie-based authentication. `serverQuery()` is not affected because it is designed to be idempotent and is invoked via GET. ### Patch The patched release enforces an Origin/Host match for non-GET action requests. Requests whose `Origin` header does not match the request's own origin are rejected with HTTP 403 unless the origin is listed in a new `allowedOrigins` configuration option. No application code changes are required for apps that invoke server actions from their own origin. Apps that legitimately invoke server actions from another origin must add those origins to the `allowedOrigins` option on `defineApp`. ### Credits Reported by `@mthx`.

Source published

24 Apr 2026 15:36:52 UTC

Source modified

13 May 2026 13:52:31 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N

Publisher rating · MODERATE