CVE-2026-33987
Description
A flaw was found in FreeRDP, a free implementation of the Remote Desktop Protocol. A memory corruption vulnerability exists in the persistent cache handling. If a memory reallocation fails, an internal size variable is incorrectly updated, while the data pointer still refers to the original, smaller memory block. This can allow a local attacker, through user interaction, to cause a denial of service or potentially execute arbitrary code.
Mitigation
To mitigate this issue, avoid connecting to untrusted Remote Desktop Protocol (RDP) servers or opening untrusted RDP files. Users can also disable persistent caching in FreeRDP by using the `--disable-persistent-caching` command-line option when launching `xfreerdp` or similar FreeRDP clients. This may impact performance for frequently accessed RDP sessions.
Common Vulnerability Scoring System (CVSS) Score Details
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).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.8 | 6.6 | 7.1 |
| Attack Vector | Local | Local | Local |
| Attack Complexity | Low | Low | Low |
| Privileges Required | None | Low | None |
| User Interaction | Required | Required | Required |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | High | None | None |
| Integrity Impact | High | High | High |
| Availability Impact | High | High | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:H
cve.org: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
Understanding the Weakness (CWE)
Integrity,Availability,Confidentiality
Technical Impact: DoS: Crash, Exit, or Restart; Execute Unauthorized Code or Commands; Read Memory; Modify Memory
If the incorrect calculation is used in the context of memory allocation, then the software may create a buffer that is smaller or larger than expected. If the allocated buffer is smaller than expected, this could lead to an out-of-bounds read or write (CWE-119), possibly causing a crash, allowing arbitrary code execution, or exposing sensitive data.
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