Critical advisory for FreeRDP

Advisory overview

FreeRDP before 3.32.2 has a use-after-free in the client's rdpgfx dynamic virtual channel: a duplicate-name channel with a new ChannelId overwrites the listener's single callback slot, which rdpgfx_on_close frees without clearing. A malicious RDP server can open and close such a channel, then send a PDU on the original channel to crash the client or potentially execute code.

Related references

• https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6wqx-rv3q-vcxp
• https://www.vulncheck.com/advisories/freerdp-before-3.32.2-use-after-free-via-rdpgfx-dynamic-virtual-channel-close
• https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6wqx-rv3q-vcxp