CVE-2026-121955 — FreeRDP
HIGHCVE-2026-121955 is a high-severity (CVSS 7.5) Use After Free vulnerability. The records list no fixed version yet; check the vendor advisory below and apply the mitigations in the meantime.
FreeRDP before 3.32.2 contains a use-after-free vulnerability in Emulate_SCardReleaseContext that frees the emulated SCardContext before its worker thread is cancelled and joined. A…
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-121955.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Description
FreeRDP before 3.32.2 contains a use-after-free vulnerability in Emulate_SCardReleaseContext that frees the emulated SCardContext before its worker thread is cancelled and joined. A malicious server can send ESTABLISHCONTEXT, a long-timeout GETSTATUSCHANGE, then RELEASECONTEXT smartcard IRPs to corrupt heap memory or crash clients using smartcard emulation.
Affected Products
freerdpfreerdpDetection & mitigation playbook
VulnerabilityDetect
Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).
Remediation status
The records we use list no fixed release for CVE-2026-121955. Check the upstream advisory for a patched version, and apply the exposure-reduction steps below in the meantime.
Mitigate without a patch
Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This vulnerability is rated as an Important severity because an untrusted RDP server can remotely cause application crashes or heap corruption without requiring elevated privileges. The flaw affects client sessions where smartcard device redirection and emulation are actively configured, which is not engaged during…
Do not enable smartcard redirection when establishing FreeRDP sessions. Ensure client connection profiles and command-line invocations omit the `/smartcard` parameter (for example, launch connections using `xfreerdp /v:<server_address>` without the `/smartcard` switch). In graphical connection managers or RDP configuration files, disable smartcard forwarding. Additionally, only establish RDP sessions to trusted endpoints. Caveats: Omitting smartcard redirection prevents the use of smartcard hardware tokens and smartcard-based authentication within the remote session. --- CME Mitigation Guidance (2026-11-06) --- Disclaimer: The following mitigation solutions are provided as a courtesy,…Source: Red Hat security advisory for CVE-2026-121955 (CC BY 4.0)
Frequently Asked Questions
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