new file mode 100644
@@ -0,0 +1,114 @@
+From da05a4039644b0821c0a61806d40688ac08f3ce0 Mon Sep 17 00:00:00 2001
+From: akallabeth <akallabeth@posteo.net>
+Date: Mon, 26 Jan 2026 12:08:48 +0100
+Subject: [PATCH] [channels,ainput] lock context when updating listener
+
+(cherry picked from commit d9ca272dce7a776ab475e9b1a8e8c3d2968c8486)
+
+CVE: CVE-2026-24683
+Upstream-Status: Backport [https://github.com/FreeRDP/FreeRDP/commit/d9ca272dce7a776ab475e9b1a8e8c3d2968c8486]
+Signed-off-by: Ankur Tyagi <ankur.tyagi85@gmail.com>
+---
+ channels/ainput/client/ainput_main.c | 36 ++++++++++++++++++++--------
+ 1 file changed, 26 insertions(+), 10 deletions(-)
+
+diff --git a/channels/ainput/client/ainput_main.c b/channels/ainput/client/ainput_main.c
+index 1a2128dcc..5f66cf90e 100644
+--- a/channels/ainput/client/ainput_main.c
++++ b/channels/ainput/client/ainput_main.c
+@@ -45,6 +45,7 @@ struct AINPUT_PLUGIN_
+ AInputClientContext* context;
+ UINT32 MajorVersion;
+ UINT32 MinorVersion;
++ CRITICAL_SECTION lock;
+ };
+
+ /**
+@@ -85,18 +86,15 @@ static UINT ainput_on_data_received(IWTSVirtualChannelCallback* pChannelCallback
+
+ static UINT ainput_send_input_event(AInputClientContext* context, UINT64 flags, INT32 x, INT32 y)
+ {
+- AINPUT_PLUGIN* ainput = NULL;
+- GENERIC_CHANNEL_CALLBACK* callback = NULL;
+ BYTE buffer[32] = { 0 };
+- UINT64 time = 0;
+ wStream sbuffer = { 0 };
+ wStream* s = Stream_StaticInit(&sbuffer, buffer, sizeof(buffer));
+
+ WINPR_ASSERT(s);
+ WINPR_ASSERT(context);
+
+- time = GetTickCount64();
+- ainput = (AINPUT_PLUGIN*)context->handle;
++ const UINT64 time = GetTickCount64();
++ AINPUT_PLUGIN* ainput = (AINPUT_PLUGIN*)context->handle;
+ WINPR_ASSERT(ainput);
+
+ if (ainput->MajorVersion != AINPUT_VERSION_MAJOR)
+@@ -105,8 +103,6 @@ static UINT ainput_send_input_event(AInputClientContext* context, UINT64 flags,
+ ainput->MajorVersion, ainput->MinorVersion);
+ return CHANNEL_RC_UNSUPPORTED_VERSION;
+ }
+- callback = ainput->base.listener_callback->channel_callback;
+- WINPR_ASSERT(callback);
+
+ {
+ char ebuffer[128] = { 0 };
+@@ -125,10 +121,15 @@ static UINT ainput_send_input_event(AInputClientContext* context, UINT64 flags,
+ Stream_SealLength(s);
+
+ /* ainput back what we have received. AINPUT does not have any message IDs. */
++ EnterCriticalSection(&ainput->lock);
++ GENERIC_CHANNEL_CALLBACK* callback = ainput->base.listener_callback->channel_callback;
++ WINPR_ASSERT(callback);
+ WINPR_ASSERT(callback->channel);
+ WINPR_ASSERT(callback->channel->Write);
+- return callback->channel->Write(callback->channel, (ULONG)Stream_Length(s), Stream_Buffer(s),
+- NULL);
++ const UINT rc = callback->channel->Write(callback->channel, (ULONG)Stream_Length(s),
++ Stream_Buffer(s), NULL);
++ LeaveCriticalSection(&ainput->lock);
++ return rc;
+ }
+
+ /**
+@@ -140,8 +141,16 @@ static UINT ainput_on_close(IWTSVirtualChannelCallback* pChannelCallback)
+ {
+ GENERIC_CHANNEL_CALLBACK* callback = (GENERIC_CHANNEL_CALLBACK*)pChannelCallback;
+
+- free(callback);
++ if (callback)
++ {
++ AINPUT_PLUGIN* ainput = (AINPUT_PLUGIN*)callback->plugin;
++ WINPR_ASSERT(ainput);
+
++ /* Lock here to ensure that no ainput_send_input_event is in progress. */
++ EnterCriticalSection(&ainput->lock);
++ free(callback);
++ LeaveCriticalSection(&ainput->lock);
++ }
+ return CHANNEL_RC_OK;
+ }
+
+@@ -155,14 +164,21 @@ static UINT init_plugin_cb(GENERIC_DYNVC_PLUGIN* base, rdpContext* rcontext, rdp
+ context->handle = (void*)base;
+ context->AInputSendInputEvent = ainput_send_input_event;
+
++ InitializeCriticalSection(&ainput->lock);
++
++ EnterCriticalSection(&ainput->lock);
+ ainput->context = context;
+ ainput->base.iface.pInterface = context;
++ LeaveCriticalSection(&ainput->lock);
+ return CHANNEL_RC_OK;
+ }
+
+ static void terminate_plugin_cb(GENERIC_DYNVC_PLUGIN* base)
+ {
+ AINPUT_PLUGIN* ainput = (AINPUT_PLUGIN*)base;
++ WINPR_ASSERT(ainput);
++
++ DeleteCriticalSection(&ainput->lock);
+ free(ainput->context);
+ }
+
@@ -30,6 +30,7 @@ SRC_URI = "git://github.com/FreeRDP/FreeRDP.git;branch=master;protocol=https \
file://CVE-2026-24680_CVE-2026-27950.patch \
file://CVE-2026-24681.patch \
file://CVE-2026-24682.patch \
+ file://CVE-2026-24683.patch \
"
S = "${WORKDIR}/git"