cbcvebase.
CVE-2026-23532
published 2026-01-19

CVE-2026-23532: FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, a client-side heap buffer overflow occurs in the FreeRDP client’s…

PriorityP259critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.43%
34.7th percentile
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, a client-side heap buffer overflow occurs in the FreeRDP client’s `gdi_SurfaceToSurface` path due to a mismatch between destination rectangle clamping and the actual copy size. A malicious server can trigger a client‑side heap buffer overflow, causing a crash (DoS) and potential heap corruption with code‑execution risk depending on allocator behavior and surrounding heap layout. Version 3.21.0 contains a patch for the issue.

Affected

3 ranges
VendorProductVersion rangeFixed in
debianfreerdp2< freerdp3 3.21.0+dfsg-1 (forky)freerdp3 3.21.0+dfsg-1 (forky)
debianfreerdp3< freerdp3 3.21.0+dfsg-1 (forky)freerdp3 3.21.0+dfsg-1 (forky)
freerdpfreerdp< 3.21.03.21.0

Detection & IOCsextracted from sources · hover to see the quote

  • Monitor FreeRDP client processes for unexpected crashes or heap corruption signals (e.g., SIGABRT, SIGSEGV) originating from the `gdi_SurfaceToSurface` code path, which may indicate exploitation attempts
  • Flag FreeRDP client connections to untrusted or unknown RDP servers; exploitation requires the client to connect to a maliciously-configured server
  • ·Debian bookworm and bullseye packages remain open (unpatched) as of the tracker update; monitor the Debian security tracker for fix availability.
  • ·Red Hat Enterprise Linux 6 will not receive a fix for this CVE.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv4.07.7HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
osv7.7HIGH
vendor_debian7.7HIGH
vendor_redhat7.7HIGH
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