CVE-2026-109948 FreeRDP CVE debrief

Who should care

Defenders responsible for FreeRDP deployments should assess exposure and prioritize patching to prevent potential memory disclosure. This vulnerability allows malicious RDP servers to read client memory, potentially impacting client memory confidentiality. Defenders should verify FreeRDP versions and apply patches if necessary. They should also review compensating controls for exposed systems while remediation is scheduled and verified.

Why it matters

Defenders should prioritize verifying FreeRDP versions and applying patches to prevent potential memory disclosure. This vulnerability allows malicious RDP servers to read client memory, potentially impacting client memory confidentiality. Defenders responsible for FreeRDP deployments should assess exposure and take action to prevent exploitation.

• Potential memory disclosure to malicious RDP servers
• Need to verify FreeRDP versions and apply patches
• Possible impact on client memory confidentiality

Technical summary

FreeRDP from 3.0.0 before 3.32.0 contains an uninitialized memory disclosure vulnerability in smartcard_Transmit_Call that allows malicious RDP servers to read client memory. Servers can send SCardTransmit requests with an invalid card handle and nonzero receive length, causing smartcard_pack_transmit_return to serialize up to 66,560 uninitialized heap bytes. This vulnerability can be triggered by malicious RDP servers, potentially impacting client memory confidentiality. Defenders should prioritize verifying FreeRDP versions and applying patches to prevent potential memory disclosure.

Defensive priority

Defenders should prioritize verifying FreeRDP versions and applying patches to prevent potential memory disclosure.

Recommended defensive actions

• Verify FreeRDP version and apply patches if necessary
• Monitor for potential malicious RDP server activity
• Implement additional security measures to prevent memory disclosure
• 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. Additional verification is needed to confirm affected versions and potential impact. Defenders should verify FreeRDP versions and apply patches if necessary. The vulnerability allows malicious RDP servers to read client memory, potentially impacting client memory confidentiality.

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.