CVE-2026-67290
Description
A flaw was found in FreeRDP. A malicious Remote Desktop Protocol (RDP) server can send specially crafted media data to a connected client. This malformed data can trigger a heap out-of-bounds read vulnerability within the TSMF FFmpeg decoder, leading to the client application crashing. This can result in a denial of service for the client.
Statement
This vulnerability in FreeRDP is rated as Important. A FreeRDP client connecting to a malicious or untrusted RDP server can be subjected to a denial of service. The flaw stems from a heap out-of-bounds read within the TSMF FFmpeg decoder when processing malformed media data, leading to client application crashes.
Mitigation
To mitigate this issue, disable the Terminal Services Multimedia Redirection (TSMF) feature when connecting to untrusted RDP servers. This prevents the vulnerable media processing from being engaged.
For `xfreerdp` clients, use the `/disable-tsmf` or `/tsmf:off` command-line option:
`xfreerdp /disable-tsmf <server_address>`
Disabling TSMF will prevent multimedia content from being redirected during the RDP session.
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).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.
Confidentiality
Technical Impact: Bypass Protection Mechanism
Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.
Other
Technical Impact: Varies by Context
The read operation could produce other undefined or unexpected results.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
