CVE-2026-121954: FreeRDP before 3.32.2 Heap Out-of-Bounds Write in Planar Codec

Q: Who is exposed to this issue?

FreeRDP clients before 3.32.2 are exposed when they connect to a malicious RDP server. The affected software entries are debian/freerdp3 and debian/freerdp2.

Q: What does an attacker need to exploit it?

An attacker needs to operate or control an RDP server that a user connects to. The server sends an oversized ResetGraphics PDU followed by a GFX PLANAR command; user interaction is required because the client must initiate or accept that connection.

Q: What is the impact of successful exploitation?

The malformed RDP traffic can cause a heap out-of-bounds write, corrupting client heap memory and crashing the FreeRDP client. The supplied severity vector rates confidentiality impact as high, with no integrity or availability impact listed.

Q: How can I determine whether a client may be affected?

Check the installed FreeRDP version and whether it is earlier than 3.32.2. Logs may show a failed ResetGraphics operation, but the issue occurs because that failure is only logged and processing can continue.

Published Nov 4, 2026

Updated

FreeRDP before 3.32.2 has a heap out-of-bounds write in the planar codec because freerdpbitmapplanarcontextreset commits new dimensions before buffer reallocation succeeds, and a failed ResetGraphics is only logged. A malicious RDP server can send an oversized ResetGraphics PDU, then a GFX PLANAR command, to corrupt client heap memory and crash the client.

Affected Software

5 affected componentsFixes available

debian/freerdp2*

debian/freerdp3*

debian/freerdp3<3.32.2+dfsg-1

3.32.2+dfsg-1

debian/freerdp2<=2.11.7+dfsg1-6~deb12u1

debian/freerdp3<=3.15.0+dfsg-2.1+deb13u3

3.32.2+dfsg-13.33.0+dfsg-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade debian/freerdp3 to a version that resolves this vulnerability.
Fixed in 3.32.2+dfsg-1
Upgrade
Upgrade debian/freerdp3 to a version that resolves this vulnerability.
Fixed in 3.32.2+dfsg-1Fixed in 3.33.0+dfsg-1

Event History

Nov 4, 2026

CVE Published

via MITRE·03:33 PM

Data Sourced

via MITRE·03:33 PM

DescriptionSeverityWeakness

Data Sourced

via NVD·04:17 PM

DescriptionSeverityWeakness

Data Sourced

via OSV·04:17 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

Who is exposed to this issue?

FreeRDP clients before 3.32.2 are exposed when they connect to a malicious RDP server. The affected software entries are debian/freerdp3 and debian/freerdp2.

What does an attacker need to exploit it?

An attacker needs to operate or control an RDP server that a user connects to. The server sends an oversized ResetGraphics PDU followed by a GFX PLANAR command; user interaction is required because the client must initiate or accept that connection.

What is the impact of successful exploitation?

The malformed RDP traffic can cause a heap out-of-bounds write, corrupting client heap memory and crashing the FreeRDP client. The supplied severity vector rates confidentiality impact as high, with no integrity or availability impact listed.

How can I determine whether a client may be affected?

Check the installed FreeRDP version and whether it is earlier than 3.32.2. Logs may show a failed ResetGraphics operation, but the issue occurs because that failure is only logged and processing can continue.

CVE-2026-121954: FreeRDP before 3.32.2 Heap Out-of-Bounds Write in Planar Codec

Affected Software

Remediation

Event History

Frequently Asked Questions

Who is exposed to this issue?

What does an attacker need to exploit it?

What is the impact of successful exploitation?

How can I determine whether a client may be affected?

Company

Resources

Contact

Frequently Asked Questions

Who is exposed to this issue?

What does an attacker need to exploit it?

What is the impact of successful exploitation?

How can I determine whether a client may be affected?