CVE-2026-121406
개요
A flaw was found in FreeRDP. A malicious Remote Desktop Protocol (RDP) server can cause a Denial of Service (DoS) by sending a specially crafted graphics payload that decompresses to zero bytes. Because the client fails to account for empty output data before initializing its internal stream buffer, an internal check fails, causing the client application to crash and terminate the active session.
내용
This vulnerability is rated as Moderate impact because exploitation is limited to a client-side denial of service and requires an active connection to an untrusted or compromised remote desktop server. In typical Red Hat Enterprise Linux environments, FreeRDP is executed as an interactive client utility rather than a persistent network service, limiting the blast radius strictly to the termination of the user's remote desktop session. Host integrity and confidentiality remain intact, as the issue results in an application abort without enabling code execution or data leakage.
완화 방법
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
CVSS (Common Vulnerability Scoring System) 점수 세부 사항
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
다음의 CVSS 지표 및 점수는 예비 정보로 검토 대상입니다.
CVSS v3 점수 분석
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| 기본 점수 | 4.3 | N/A | 4.3 |
| 공격 벡터 | Network | N/A | Network |
| 공격 복잡성 | Low | N/A | Low |
| 필요한 권한 | None | N/A | None |
| 사용자 상호 작용 | Required | N/A | Required |
| 범위 | Unchanged | N/A | Unchanged |
| 기밀성 | None | N/A | None |
| 무결성에 미치는 영향 | None | N/A | None |
| 가용성에 미치는 영향 | Low | N/A | Low |
벡터
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
취약점 이해 (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart
While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, an attacker can still cause a denial of service if they can trigger an assert statement, and if the scope of the assert() extends beyond the attacker's own session. For example, if a server handles multiple simultaneous connections, if an assert() occurs in one single connection that causes all other connections to be dropped, this could be a significant denial of service.
