CVE-2026-104873 langchain-ai CVE debrief

Who should care

Python developers and administrators using langgraph-sdk, especially those with resource-scoped authorization decorators, should verify and apply patch 0.4.4. They should review deployments for potential authorization bypass and implement additional authorization checks if necessary. This includes verifying patch application, reviewing authorization checks, and ensuring system security and data integrity.

Why it matters

CVE-2026-104873 allows authenticated users to perform actions the application intended to deny due to incorrect application of actions= argument on resource-scoped authorization decorators in langgraph-sdk. Python developers and administrators should verify and apply patch 0.4.4, review deployments for potential authorization bypass, and implement additional authorization checks if necessary.

• Potential authorization bypass, allowing unintended actions.
• Possible exposure of sensitive data or functionality.
• Need for verification of patch application and authorization checks.
• Potential impact on system security and data integrity.

Technical summary

The langgraph-sdk incorrectly applies the actions= argument on resource-scoped authorization decorators, potentially allowing authenticated users to perform actions the application intended to deny. This affects Python deployments using langgraph-sdk with resource-scoped authorization decorators. The patch version 0.4.4 fixes this issue. Review and apply the patch, verify deployments, and implement additional authorization checks if necessary. The vulnerability allows unintended actions, including reading, updating, or deleting another user's resource.

Defensive priority

Python developers using langgraph-sdk should verify and apply the patch to prevent unintended authorization bypass.

Recommended defensive actions

• Verify the langgraph-sdk version and apply patch 0.4.4 if using affected versions.
• Review Python deployments using actions= on resource-scoped decorators for potential authorization bypass.
• Implement additional authorization checks if the affected handler does not independently enforce necessary action, ownership, or permission checks.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• 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.

Evidence notes

The langgraph-sdk incorrectly applies the actions= argument on resource-scoped authorization decorators. This may allow authenticated users to perform actions the application intended to deny. Evidence is based on the CVE record and source item details. Defensive verification tasks include reviewing patch application, verifying authorization checks, and implementing additional checks if necessary. The affected versions and patch details are provided in the CVE record and source references.

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.