CVE-2026-65976 deskflow CVE debrief

Who should care

Defenders responsible for systems using Deskflow versions between 1.17.0 and 1.26.0.300 should assess exposure and prioritize verification and remediation efforts. Those responsible for system security, particularly those managing Deskflow deployments, should review system configurations, verify versions, and implement compensating controls as needed.

Why it matters

Defenders should care about CVE-2026-65976 because it allows a connected peer to exhaust receiver memory by sending repeated DCLP DataChunk messages, potentially leading to denial-of-service (DoS) attacks. Those responsible for systems using Deskflow versions between 1.17.0 and 1.26.0.300 should assess exposure, prioritize verification and remediation efforts, and implement compensating controls.

• Memory exhaustion due to repeated DCLP DataChunk messages
• Potential for denial-of-service (DoS) attacks
• Need for verification of Deskflow version and exposure
• Prioritization of remediation efforts for affected systems

Technical summary

The vulnerability allows a connected peer to send repeated DCLP DataChunk messages to ClipboardChunk::assemble() in src/lib/deskflow/ClipboardChunk.cpp, causing the server path in src/lib/server/ClientProxy1_6.cpp or client path in src/lib/client/ServerProxy.cpp to append data beyond the DataStart declared size and configured clipboard limit before DataEnd validation, exhausting receiver memory. This issue affects Deskflow versions between 1.17.0 and 1.26.0.300, and is fixed in continuous build 1.26.0.300. Defenders should prioritize verifying exposure and assessing the impact of this vulnerability on their systems.

Defensive priority

Defenders should prioritize verifying exposure and assessing the impact of this vulnerability on their systems, especially those using Deskflow versions between 1.17.0 and 1.26.0.300.

Recommended defensive actions

• Verify exposure by checking the Deskflow version and ensuring it is 1.26.0.300 or later
• Assess the impact of this vulnerability on systems using Deskflow versions between 1.17.0 and 1.26.0.300
• Implement compensating controls, such as monitoring for suspicious activity
• Review relevant 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
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed

Evidence notes

The CVE record and NVD vulnerability detail page provide information about the vulnerability, including its description, CVSS score, and affected versions. Defenders should verify Deskflow versions between 1.17.0 and 1.26.0.300 and assess exposure. Evidence from the CVE Program and NVD detail page indicates a connected peer can send repeated DCLP DataChunk messages, causing memory exhaustion. Limited source detail suggests verifying system configurations and monitoring for suspicious activity.

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.