CVE-2026-42190 redwoodjs CVE debrief

Who should care

Defenders responsible for RedwoodSDK deployments, particularly those using versions between 1.0.0-beta.50 and 1.2.2, should assess their exposure and apply the patch in version 1.2.3. This vulnerability may impact applications relying on server actions for sensitive operations.

Why it matters

CVE-2026-42190 is a CSRF vulnerability in RedwoodSDK that allows attackers to invoke server actions with a victim's session cookie. Defenders should verify their inventory, apply the patch, and monitor for potential attacks.

• Potential unauthorized invocation of server actions
• Possible use of victim's session cookie for malicious actions
• Requires verification of inventory and application of patch
• May impact applications with sensitive operations relying on server actions

Technical summary

The RedwoodSDK, a server-first React framework, is vulnerable to cross-site request forgery (CSRF) attacks due to a lack of origin validation in server actions. This issue exists in versions from 1.0.0-beta.50 to before 1.2.3. An attacker can exploit this by making a request from a different origin that the browser treats as same-site, potentially allowing them to invoke server actions with a victim's session cookie attached.

Defensive priority

Defenders should prioritize verifying their inventory of RedwoodSDK versions and applying the patch in version 1.2.3 to prevent potential CSRF attacks.

Recommended defensive actions

• Verify and update RedwoodSDK to version 1.2.3 or later
• Review and implement CSRF protection measures for server actions
• Monitor for potential CSRF attacks
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its CVSS score of 5.3 and MEDIUM severity. The issue is patched in version 1.2.3. There is limited information available on the specific impacts and affected scope. Defenders should verify their inventory, review the official advisory, and monitor for potential attacks. The browser's same-site origin policy and session cookie handling are crucial factors in this vulnerability.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.