Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.28.0, rdpsnd_server_recv_formats in channels/rdpsnd/server/rdpsnd_main.c frees context->client_formats on a malformed Client Audio Formats PDU without clearing the owning pointer or num_client_formats. An authenticated RDP client can trigger an error such as a cbSize larger than the remaining record, leave the dangling pointer in the server context, and cause rdpsnd_server_context_free to free the same allocation again at session teardown. This reliably terminates the server and can create allocator-dependent heap corruption. This issue is fixed in version 3.28.0.
Affected products
freerdp: freerdp
References5
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-9g22-w2gr-v… ExploitMitigationVendor Advisory
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-9g22-w2gr-v… ExploitMitigationVendor Advisory
- github.com/FreeRDP/FreeRDP/commit/caf653c0ba1c75ec8f298d1baa597… Patch
- github.com/FreeRDP/FreeRDP/pull/12993 Issue TrackingPatch
- github.com/FreeRDP/FreeRDP/releases/tag/3.28.0 Release Notes
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
7.1
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/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 - EPSS — exploit probability
- 1% percentile: 48 · as of 10 November 2026
- CWE
- CWE-415
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