Vulnerability · Published Mar 30, 2026 · Assigned by GitHub_M

CVE-2026-33984FreeRDP: ClearCodec resize_vbar_entry() Heap OOB Write

High 7.5

In plain English

A high-severity heap buffer overflow in FreeRDP from FreeRDP. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 35% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.4%top 65.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, in resize_vbar_entry() in libfreerdp/codec/clear.c, vBarEntry->size is updated to vBarEntry->count before the winpr_aligned_recalloc() call. If realloc fails, size is inflated while pixels still points to the old, smaller buffer. On a subsequent call where count <= size (the inflated value), realloc is skipped. The caller then writes count * bpp bytes of attacker-controlled pixel data into the undersized buffer, causing a heap buffer overflow. This issue has been patched in version 3.24.2.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10freerdp2:3.10.3-5.el10_1.6ALSA-2026:8458
AlmaLinux:8freerdp2:2.11.7-7.el8_10ALSA-2026:8945
AlmaLinux:9freerdp2:2.11.7-1.el9_7.6ALSA-2026:8457
AlmaLinux:10freerdp-devel2:3.10.3-5.el10_1.6ALSA-2026:8458
AlmaLinux:8freerdp-devel2:2.11.7-7.el8_10ALSA-2026:8945
AlmaLinux:9freerdp-devel2:2.11.7-1.el9_7.6ALSA-2026:8457
AlmaLinux:10freerdp-libs2:3.10.3-5.el10_1.6ALSA-2026:8458
AlmaLinux:8freerdp-libs2:2.11.7-7.el8_10ALSA-2026:8945
AlmaLinux:9freerdp-libs2:2.11.7-1.el9_7.6ALSA-2026:8457
AlmaLinux:10freerdp-server2:3.10.3-5.el10_1.6ALSA-2026:8458
AlmaLinux:10libwinpr2:3.10.3-5.el10_1.6ALSA-2026:8458
AlmaLinux:8libwinpr2:2.11.7-7.el8_10ALSA-2026:8945
AlmaLinux:9libwinpr2:2.11.7-1.el9_7.6ALSA-2026:8457
AlmaLinux:10libwinpr-devel2:3.10.3-5.el10_1.6ALSA-2026:8458
AlmaLinux:8libwinpr-devel2:2.11.7-7.el8_10ALSA-2026:8945
AlmaLinux:9libwinpr-devel2:2.11.7-1.el9_7.6ALSA-2026:8457
Alpine:v3.23freerdp3.24.2-r0ALPINE-CVE-2026-33984
Alpine:v3.24freerdp3.24.2-r0ALPINE-CVE-2026-33984
Debian:12freerdp2no fix listedDEBIAN-CVE-2026-33984
Debian:13freerdp33.15.0+dfsg-2.1+deb13u2DEBIAN-CVE-2026-33984
Debian:14freerdp33.24.2+dfsg-1DEBIAN-CVE-2026-33984
Rocky Linux:10freerdp2:3.10.3-5.el10_1.6RLSA-2026:8458
Rocky Linux:8freerdp2:2.11.7-7.el8_10RLSA-2026:8945
Rocky Linux:9freerdp2:2.11.7-1.el9_7.6RLSA-2026:8457
Ubuntu:22.04:LTSfreerdp2no fix listedUBUNTU-CVE-2026-33984
Ubuntu:24.04:LTSfreerdp33.30.0+dfsg-0ubuntu0.24.04.1USN-8561-1
Ubuntu:24.04:LTSfreerdp33.30.0+dfsg-0ubuntu0.24.04.1UBUNTU-CVE-2026-33984
Ubuntu:25.10freerdp3no fix listedUBUNTU-CVE-2026-33984
Ubuntu:26.04:LTSfreerdp33.30.0+dfsg-0ubuntu0.26.04.1USN-8561-1

Affected products (as reported)

VendorProductVersions
FreeRDP FreeRDP < 3.24.2

Weakness: CWE-122, CWE-131 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

References