2.4
LOW CVSS 4.0
CVE-2026-66401
FreeRDP before 3.29.0 Out-of-Bounds Read via UVC H.264
Description

FreeRDP before 3.29.0 contains an out-of-bounds heap read vulnerability in the UVC H.264 extension-unit parser that fails to validate descriptor length before accessing the GUID field. A local attacker with a malicious USB video camera can trigger a heap read beyond allocated bounds during camera stream setup, causing denial of service.

INFO

Published Date :

Aug. 1, 2026, 1:16 p.m.

Last Modified :

Sept. 3, 2026, 7:45 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-66401 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Freerdp freerdp
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 LOW 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 LOW [email protected]
CVSS 3.1 LOW MITRE-CVE
CVSS 4.0 LOW 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 LOW [email protected]
Solution
Update FreeRDP to version 3.29.0 or later to fix heap read vulnerability.
  • Update FreeRDP to version 3.29.0 or later.
  • Apply vendor-provided patches for the UVC parser.
  • Validate descriptor length in the UVC parser.
  • Disable UVC H.264 extension if possible.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-66401.

URL Resource
https://github.com/FreeRDP/FreeRDP/commit/5044d5390035c6fd9a36ad885192d97d21e8a92d Patch
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-8jj2-67pg-j6mg Exploit Patch Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-before-out-of-bounds-read-via-uvc-h-264 Patch Third Party Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-8jj2-67pg-j6mg Exploit Patch Vendor Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-66401 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-66401 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-66401 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-66401 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Sep. 03, 2026

    Action Type Old Value New Value
    Added CPE Configuration OR *cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:* versions up to (excluding) 3.29.0
    Added Reference Type VulnCheck: https://github.com/FreeRDP/FreeRDP/commit/5044d5390035c6fd9a36ad885192d97d21e8a92d Types: Patch
    Added Reference Type VulnCheck: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-8jj2-67pg-j6mg Types: Exploit, Patch, Vendor Advisory
    Added Reference Type VulnCheck: https://www.vulncheck.com/advisories/freerdp-before-out-of-bounds-read-via-uvc-h-264 Types: Patch, Third Party Advisory
    Added Reference Type CISA-ADP: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-8jj2-67pg-j6mg Types: Exploit, Patch, Vendor Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 03, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-8jj2-67pg-j6mg
    Added SSVC {'id': 'CVE-2026-66401', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-03T17:41:04.555664Z'}
  • New CVE Received by [email protected]

    Aug. 01, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'FreeRDP', 'product': 'FreeRDP', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.29.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '3.29.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}]
    Added Description FreeRDP before 3.29.0 contains an out-of-bounds heap read vulnerability in the UVC H.264 extension-unit parser that fails to validate descriptor length before accessing the GUID field. A local attacker with a malicious USB video camera can trigger a heap read beyond allocated bounds during camera stream setup, causing denial of service.
    Added CVSS V4.0 AV:P/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:P/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
    Added CWE CWE-125
    Added Reference https://github.com/FreeRDP/FreeRDP/commit/5044d5390035c6fd9a36ad885192d97d21e8a92d
    Added Reference https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-8jj2-67pg-j6mg
    Added Reference https://www.vulncheck.com/advisories/freerdp-before-out-of-bounds-read-via-uvc-h-264
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.