Is CVE-2026-26955 actively exploited?

No active exploitation of CVE-2026-26955 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-26955 be exploited remotely?

Yes. CVE-2026-26955 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-26955?

CVE-2026-26955 has a CVSS score of 8.8 (HIGH) and an EPSS exploitation probability of 0.04%.

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HIGH

CVE-2026-26955

CWE-787Published: February 25, 2026· Updated: Feb 27, 2026

8.8

CVSS v3.1

EPSS:0.04%probability of exploitation in 30 daysPercentile:12.7th

Official Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, a malicious RDP server can trigger a heap buffer overflow in FreeRDP clients using the GDI surface pipeline (e.g., `xfreerdp`) by sending an RDPGFX ClearCodec surface command with an out-of-bounds destination rectangle. The `gdi_SurfaceCommand_ClearCodec()` handler does not call `is_within_surface()` to validate the command rectangle against the destination surface dimensions, allowing attacker-controlled `cmd->left`/`cmd->top` (and subcodec rectangle offsets) to reach image copy routines that write into `surface->data` without bounds enforcement. The OOB write corrupts an adjacent `gdiGfxSurface` struct's `codecs*` pointer with attacker-controlled pixel data, and corruption of `codecs*` is sufficient to reach an indirect function pointer call (`NSC_CONTEXT.decode` at `nsc.c:500`) on a subsequent codec command — full instruction pointer (RIP) control demonstrated in exploitability harness. Users should upgrade to version 3.23.0 to receive a patch.

NVD Source

Technical Analysis

CVE-2026-26955 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 8.8.

From a weakness classification perspective (CWE-787): Out-of-bounds write vulnerabilities can lead to data corruption, crashes, or arbitrary code execution.