CVE-2026-59324 Spring CVE debrief

Who should care

Organizations using Spring Integration, especially those with IntegrationFlow configurations using .fluxTransform(), should be aware of this vulnerability and take necessary actions to protect their systems. This includes reviewing and updating IntegrationFlow configurations, monitoring for suspicious activity, and applying patches for affected versions. Security teams and operators should prioritize patching to prevent potential data breaches and security incidents.

Technical summary

The vulnerability occurs when using .fluxTransform() with an asynchronous/reordering fluxFunction that emits raw payloads in IntegrationFlow. Concurrent requests on the same FluxMessageChannel subscription have their reply headers (replyChannel, errorChannel, correlationId, and propagated security/tenant headers) copied from the most recently consumed upstream message. This issue affects multiple Spring Integration versions, including 5.5.21 and earlier, 6.4.0 - 6.4.12, 6.5.0 - 6.5.10, 7.0.0 - 7.0.5, and 7.1.0. The affected product deployments should be reviewed for potential exposure.

Defensive priority

Organizations using affected Spring Integration versions should prioritize patching to prevent potential data breaches and security incidents.

Recommended defensive actions

• Apply patches for affected Spring Integration versions
• Review and update IntegrationFlow configurations to prevent exploitation
• Monitor for suspicious activity on FluxMessageChannel subscriptions
• 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 indicates that when an IntegrationFlow uses .fluxTransform() with an asynchronous/reordering fluxFunction that emits raw payloads, concurrent requests on the same FluxMessageChannel subscription have their reply headers copied from the most recently consumed upstream message. This issue affects various Spring Integration versions, including 5.5.21 and earlier, 6.4.0 - 6.4.12, 6.5.0 - 6.5.10, 7.0.0 - 7.0.5, and 7.1.0.

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.