CVE-2026-33952
FreeRDP: DoS via WINPR_ASSERT in rts_read_auth_verifier_no_checks
Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, an unvalidated auth_length field read from the network triggers a WINPR_ASSERT() failure in rts_read_auth_verifier_no_checks(), causing any FreeRDP client connecting through a malicious RDP Gateway to crash with SIGABRT. This is a pre-authentication denial of service affecting all FreeRDP clients using RPC-over-HTTP gateway transport. The assertion is active in default release builds (WITH_VERBOSE_WINPR_ASSERT=ON). This issue has been patched in version 3.24.2.
INFO
Published Date :
March 30, 2026, 10:16 p.m.
Last Modified :
March 30, 2026, 10:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-33952
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.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update FreeRDP clients to version 3.24.2 or later.
- Ensure the WINPR_ASSERT macro is properly configured.
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-2026-33952.
| URL | Resource |
|---|---|
| https://github.com/FreeRDP/FreeRDP/commit/4ac0b6467d371a1ad47c1f751c5b305e4c068adb | |
| https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-4v4p-9v5x-hc93 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-33952 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-2026-33952
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-2026-33952 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-33952 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]
Mar. 30, 2026
Action Type Old Value New Value Added Description FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, an unvalidated auth_length field read from the network triggers a WINPR_ASSERT() failure in rts_read_auth_verifier_no_checks(), causing any FreeRDP client connecting through a malicious RDP Gateway to crash with SIGABRT. This is a pre-authentication denial of service affecting all FreeRDP clients using RPC-over-HTTP gateway transport. The assertion is active in default release builds (WITH_VERBOSE_WINPR_ASSERT=ON). This issue has been patched in version 3.24.2. Added CVSS V4.0 AV:N/AC:H/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 CWE CWE-617 Added Reference https://github.com/FreeRDP/FreeRDP/commit/4ac0b6467d371a1ad47c1f751c5b305e4c068adb Added Reference https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-4v4p-9v5x-hc93