CVE-2026-33983 MEDIUM

CVE-2026-33983: FreeRDP: Progressive Codec Quant BYTE Underflow - UB + CPU DoS

Vendor Freerdp
Product FreeRDP
Weakness CWE-190
Published March 30, 2026
Last update June 30, 2026
View on NVD All CVEs

CVSS base score

6.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction Required
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

March 30, 2026 CVE published
June 30, 2026 Record updated