CVE-2026-104973 makeplane CVE debrief

Who should care

Defenders responsible for open-source project management tools, specifically Plane, should assess exposure and apply the patch if necessary. This includes security teams, IT administrators, and developers using Plane in their environments. The vulnerability affects Plane's webhook delivery mechanism, allowing attackers to bypass SSRF protections. Defenders should prioritize verifying exposure and applying the patch to prevent potential SSRF exploitation.

Why it matters

CVE-2026-104973 is a high-severity vulnerability in Plane, allowing DNS rebinding attacks that could enable SSRF exploitation. Defenders should prioritize verifying exposure and applying the patch.

• Potential SSRF exploitation through DNS rebinding
• Unauthorized access to internal resources
• Need for verification of exposure and patch application
• Possible impact on systems using Plane for project management

Technical summary

The Plane open-source project management tool is vulnerable to a DNS rebinding attack, which bypasses the fix for CVE-2026-30242. This allows for potential SSRF exploitation. The issue was addressed in version 1.4.0. The vulnerability affects the webhook delivery mechanism in Plane, enabling attackers to bypass SSRF protections. The vulnerability has a high CVSS score of 7.6, indicating significant risk. Defenders should prioritize verifying exposure and applying the patch. The vulnerability was publicly disclosed on October 5, 2026.

Defensive priority

Defenders should prioritize verifying exposure and applying the patch, as DNS rebinding could allow unauthorized access.

Recommended defensive actions

• Verify if the Plane tool is used in the environment and assess exposure.
• Check if the version is older than 1.4.0 and apply the patch if necessary.
• Monitor for potential SSRF exploitation attempts.
• 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 source item provide details on the vulnerability and its fix. However, limited information is available on potential exploitation or impact. The vulnerability was publicly disclosed on October 5, 2026, and has not been modified since then. There are no known instances of exploitation, but defenders should verify exposure and apply the patch. The Plane project management tool is used by various organizations, and its users should prioritize patching.

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.