CVSS 4.0
8.2 highCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCVE-2026-121963
High (8.2).
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FreeRDP before 3.32.2 contains a use-after-free vulnerability in the asynchronous dynamic rdpsnd channel that allows malicious RDP servers to trigger freed callback access by closing the channel with queued audio PDUs. Attackers can send a training PDU then close the channel so the playback thread reads the freed callback in rdpsnd_virtual_channel_write, crashing the client.
Severity
CVSS 3.1
5.9 mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H- CISA's assessment (SSVC)
- Exploitation: PoC · Automatable: no · Technical impact: partial, assessed 2026-11-04. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)
- OWASP Top 10
- A06:2025 Insecure Design
- Published
- Modified
- Record from
- the NVD, synced
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Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| FreeRDP | before 3.32.2 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12 | freerdp2 | no fix listed | DEBIAN-CVE-2026-121963 |
| Debian | 13 | freerdp3 | no fix listed | DEBIAN-CVE-2026-121963 |
| Debian | 14 | freerdp3 | 3.32.2+dfsg-1 | DEBIAN-CVE-2026-121963 |
From the distributions' data via OSV.dev: the Debian Security Tracker. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian.
Attack patterns (CAPEC)
- CAPEC-26 Leveraging Race Conditions Likelihood: High · Severity: High
- CAPEC-29 Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions Likelihood: High · Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.