Vulnerability · Published Mar 30, 2026 · Assigned by GitHub_M
CVE-2026-33983FreeRDP: Progressive Codec Quant BYTE Underflow - UB + CPU DoS
Medium 6.5
In plain English
A medium-severity integer 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 39% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, progressive_decompress_tile_upgrade() detects a mismatch via progressive_rfx_quant_cmp_equal() but only emits WLog_WARN, execution continues. The wrapped value (247) is used as a shift exponent, causing undefined behavior and an approximately 80 billion iteration loop (CPU DoS). This issue has been patched in version 3.24.2.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:10 | freerdp | 2:3.10.3-5.el10_1.6 | ALSA-2026:8458 |
| AlmaLinux:8 | freerdp | 2:2.11.7-7.el8_10 | ALSA-2026:8945 |
| AlmaLinux:9 | freerdp | 2:2.11.7-1.el9_7.6 | ALSA-2026:8457 |
| AlmaLinux:10 | freerdp-devel | 2:3.10.3-5.el10_1.6 | ALSA-2026:8458 |
| AlmaLinux:8 | freerdp-devel | 2:2.11.7-7.el8_10 | ALSA-2026:8945 |
| AlmaLinux:9 | freerdp-devel | 2:2.11.7-1.el9_7.6 | ALSA-2026:8457 |
| AlmaLinux:10 | freerdp-libs | 2:3.10.3-5.el10_1.6 | ALSA-2026:8458 |
| AlmaLinux:8 | freerdp-libs | 2:2.11.7-7.el8_10 | ALSA-2026:8945 |
| AlmaLinux:9 | freerdp-libs | 2:2.11.7-1.el9_7.6 | ALSA-2026:8457 |
| AlmaLinux:10 | freerdp-server | 2:3.10.3-5.el10_1.6 | ALSA-2026:8458 |
| AlmaLinux:10 | libwinpr | 2:3.10.3-5.el10_1.6 | ALSA-2026:8458 |
| AlmaLinux:8 | libwinpr | 2:2.11.7-7.el8_10 | ALSA-2026:8945 |
| AlmaLinux:9 | libwinpr | 2:2.11.7-1.el9_7.6 | ALSA-2026:8457 |
| AlmaLinux:10 | libwinpr-devel | 2:3.10.3-5.el10_1.6 | ALSA-2026:8458 |
| AlmaLinux:8 | libwinpr-devel | 2:2.11.7-7.el8_10 | ALSA-2026:8945 |
| AlmaLinux:9 | libwinpr-devel | 2:2.11.7-1.el9_7.6 | ALSA-2026:8457 |
| Alpine:v3.23 | freerdp | 3.24.2-r0 | ALPINE-CVE-2026-33983 |
| Alpine:v3.24 | freerdp | 3.24.2-r0 | ALPINE-CVE-2026-33983 |
| Debian:12 | freerdp2 | no fix listed | DEBIAN-CVE-2026-33983 |
| Debian:13 | freerdp3 | 3.15.0+dfsg-2.1+deb13u2 | DEBIAN-CVE-2026-33983 |
| Debian:14 | freerdp3 | 3.24.2+dfsg-1 | DEBIAN-CVE-2026-33983 |
| Rocky Linux:10 | freerdp | 2:3.10.3-5.el10_1.6 | RLSA-2026:8458 |
| Rocky Linux:8 | freerdp | 2:2.11.7-7.el8_10 | RLSA-2026:8945 |
| Rocky Linux:9 | freerdp | 2:2.11.7-1.el9_7.6 | RLSA-2026:8457 |
| Ubuntu:22.04:LTS | freerdp2 | no fix listed | UBUNTU-CVE-2026-33983 |
| Ubuntu:24.04:LTS | freerdp3 | 3.30.0+dfsg-0ubuntu0.24.04.1 | USN-8561-1 |
| Ubuntu:24.04:LTS | freerdp3 | 3.30.0+dfsg-0ubuntu0.24.04.1 | UBUNTU-CVE-2026-33983 |
| Ubuntu:25.10 | freerdp3 | no fix listed | UBUNTU-CVE-2026-33983 |
| Ubuntu:26.04:LTS | freerdp3 | 3.30.0+dfsg-0ubuntu0.26.04.1 | USN-8561-1 |
Affected products (as reported)
Weakness: CWE-190, CWE-252 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
References
- https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-4gfm-4p52-h478 x_refsource_CONFIRM
- https://github.com/FreeRDP/FreeRDP/commit/78188ab479c8e6eb9ba2475b3732c76b4bbe5425 x_refsource_MISC
- https://access.redhat.com/security/cve/CVE-2026-33983 vdb-entry, x_refsource_REDHAT
- RHBZ#2453220 issue-tracking, x_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33983.json x_sadp-csaf-vex
- https://access.redhat.com/errata/RHSA-2026:11333 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:8458 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19033 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:8945 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:11651 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:11649 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:12388 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:12359 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:11332 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:11336 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:10709 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:9656 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:8457 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19349 vendor-advisory, x_refsource_REDHAT