7.1
HIGH CVSS 4.0
CVE-2026-121959
FreeRDP before 3.32.2 Infinite Loop via Truncated WebSocket Frame
Description

FreeRDP before 3.32.2 contains an infinite loop vulnerability in websocket_context_read that fails to handle a zero BIO result with payload outstanding. A malicious RD Gateway can send a truncated WebSocket frame followed by a TLS close_notify, causing a client thread to spin and consume CPU until killed.

INFO

Published Date :

Nov. 4, 2026, 4:17 p.m.

Last Modified :

Nov. 4, 2026, 4:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-121959 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 3.1 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Update FreeRDP to version 3.32.2 or later to fix infinite loop in websocket_context_read.
  • Update FreeRDP to version 3.32.2 or later.
  • Apply vendor-provided patches for affected versions.
  • Monitor system CPU usage.
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-2026-121959.

URL Resource
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-x26g-fp9v-c2pg
https://www.vulncheck.com/advisories/freerdp-before-3.32.2-infinite-loop-via-truncated-websocket-frame
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-121959 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-2026-121959 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-2026-121959 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-121959 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.

  • New CVE Received by [email protected]

    Nov. 04, 2026

    Action Type Old Value New Value
    Added Description FreeRDP before 3.32.2 contains an infinite loop vulnerability in websocket_context_read that fails to handle a zero BIO result with payload outstanding. A malicious RD Gateway can send a truncated WebSocket frame followed by a TLS close_notify, causing a client thread to spin and consume CPU until killed.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/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:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
    Added CWE CWE-835
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/121xxx/CVE-2026-121959.json">CVE-2026-121959</a>
    Added Reference https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-x26g-fp9v-c2pg
    Added Reference https://www.vulncheck.com/advisories/freerdp-before-3.32.2-infinite-loop-via-truncated-websocket-frame
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.