CVE-2026-56297
FreeRDP - Use-After-Free via Race Condition in DRDYNVC Channel Callback
Description
FreeRDP before 3.22.0 contains a use-after-free vulnerability in dvcman_channel_close and dvcman_call_on_receive due to improper synchronization of channel_callback access. A malicious RDP server can trigger a race condition by sending DYNVC_DATA and DYNVC_CLOSE messages concurrently, causing heap-use-after-free in the drdynvc client thread and potentially enabling remote code execution or denial of service.
INFO
Published Date :
July 8, 2026, 2:17 p.m.
Last Modified :
July 10, 2026, 2:36 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | MITRE-CVE | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update FreeRDP to version 3.22.0 or later.
- Apply vendor patches for synchronization issues.
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-2026-56297.
| URL | Resource |
|---|---|
| https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mv2-5q57-2v8h | Exploit Vendor Advisory |
| https://www.vulncheck.com/advisories/freerdp-use-after-free-via-race-condition-in-drdynvc-channel-callback | Third Party Advisory |
| https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mv2-5q57-2v8h | Exploit 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-2026-56297 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-2026-56297
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-2026-56297 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-56297 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]
Jul. 10, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Added CPE Configuration OR *cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:* versions up to (excluding) 3.22.0 Added Reference Type VulnCheck: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mv2-5q57-2v8h Types: Exploit, Vendor Advisory Added Reference Type VulnCheck: https://www.vulncheck.com/advisories/freerdp-use-after-free-via-race-condition-in-drdynvc-channel-callback Types: Third Party Advisory Added Reference Type CISA-ADP: https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mv2-5q57-2v8h Types: Exploit, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 08, 2026
Action Type Old Value New Value Added Reference https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mv2-5q57-2v8h Added SSVC {'id': 'CVE-2026-56297', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-08T14:22:55.790096Z'} -
New CVE Received by [email protected]
Jul. 08, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'FreeRDP', 'product': 'FreeRDP', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.22.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '3.22.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}] Added Description FreeRDP before 3.22.0 contains a use-after-free vulnerability in dvcman_channel_close and dvcman_call_on_receive due to improper synchronization of channel_callback access. A malicious RDP server can trigger a race condition by sending DYNVC_DATA and DYNVC_CLOSE messages concurrently, causing heap-use-after-free in the drdynvc client thread and potentially enabling remote code execution or denial of service. Added CVSS V4.0 AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/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:H/PR:N/UI:N/S:U/C:L/I:L/A:H Added CWE CWE-362 Added Reference https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mv2-5q57-2v8h Added Reference https://www.vulncheck.com/advisories/freerdp-use-after-free-via-race-condition-in-drdynvc-channel-callback