FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, FreeRDP clients that negotiate RDPGFX AVC444 with an H.264 decoder backend calculate the intermediate YUV444 allocation size in libfreerdp/codec/h264.c with 32-bit multiplication in avc444_ensure_buffer. A malicious RDP server can supply surface dimensions for which piDstStride multiplied by padDstHeight wraps to a small nonzero value, causing winpr_aligned_recalloc to allocate an undersized buffer before YUV420CombineToYUV444 writes using the actual stride and rectangle dimensions. This can cause a client crash and may permit code execution through attacker-influenced heap corruption. This issue is fixed in version 3.27.0.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, freerdp_image_copy_from_icon_data in libfreerdp/codec/color.c calculates nWidth multiplied by nHeight multiplied by FreeRDPGetBytesPerPixel(format) in 32-bit arithmetic. A malicious RDP server can send a RAIL TS_ICON_INFO update with dimensions such as 32768 by 32768 and 32 bits per pixel so the required-size calculation wraps, bypassing the cbBitsColor source bounds check before freerdp_image_copy_no_overlap reads attacker-controlled icon data. This affects RemoteApp clients using the vulnerable library path, while xfreerdp has a caller-side mitigation. This issue is fixed in version 3.27.0.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.30.0, FreeRDP's winpr/libwinpr/sspi/Kerberos/kerberos.c kerberos_DecryptMessage function fails to bound the peer-controlled GSS Wrap-token EC field before using it with RRC in IOV pointer offsets, allowing a malicious RDP peer to trigger out-of-bounds reads and in-place writes during CredSSP/NLA Kerberos decryption. This issue is fixed in version 3.30.0.

FreeRDP before 3.30.0 contains a server-side authentication bypass in the RDSTLS handshake. When a server is configured with RdstlsSecurity = TRUE, the handshake dispatches inbound PDUs based solely on the attacker-supplied wire pduType without verifying that the received PDU is the one required at the current step. Because the rdpRdstls object is calloc-zeroed, its resultCode defaults to 0 (RDSTLS_RESULT_SUCCESS). An unauthenticated remote client can send a Capabilities PDU instead of the required Authentication Request PDU; rdstls_process_capabilities() returns success without ever setting resultCode, so the server responds with an AUTHRSP carrying resultCode SUCCESS and treats the session as authenticated without evaluating any password, redirection GUID, or auto-reconnect cookie. This affects the released FreeRDP 3.x series (e.g., 3.27.1) and master HEAD; at the time of the advisory no patched version was available.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.30.0, FreeRDP server-side RDSTLS in libfreerdp/core/rdstls.c accepts an attacker-supplied RDSTLS_TYPE_CAPABILITIES PDU while rdstls_server_authenticate is waiting for RDSTLS_TYPE_AUTHREQ, leaving resultCode at RDSTLS_RESULT_SUCCESS and allowing a remote unauthenticated client to bypass the RedirectionGuid, username, domain, or password checks. This issue is fixed in version 3.30.0.

FreeRDP before 3.30.0 contains an out-of-bounds vulnerability in kerberos_DecryptMessage() (winpr/libwinpr/sspi/Kerberos/kerberos.c). The 16-bit EC (extra count) field of a peer-supplied GSS Wrap token (RFC 4121) is used directly in pointer arithmetic to locate the encrypted regions without being bounds-checked, while only RRC and the total buffer length are validated. A malicious peer (server or client) can supply a large EC value (up to 0xFFFF) during CredSSP/NLA authentication, moving the decrypt operation's base pointers past the end of the ~60-byte token buffer. Because the AES-CTS-HMAC enctypes decrypt in place before the HMAC integrity check, this results in an out-of-bounds read and in-place out-of-bounds write, potentially leading to information disclosure, memory corruption, or denial of service.

FreeRDP before 3.30.0 (<= 3.29.0) contains a heap-based buffer overflow in the Windows clipboard client's CliprdrStream_Read function (client/Windows/wf_cliprdr.c). When an OLE paste consumer (e.g. explorer.exe) calls IStream::Read with a fixed-size buffer of cb bytes, CliprdrStream_Read requests file contents from the RDP server and then copies the response into the caller's buffer using the server-supplied length (req_fsize) instead of cb. A malicious or compromised RDP server can return an oversized CB_FILECONTENTS_RESPONSE, causing an out-of-bounds write of attacker-controlled data into the paste consumer's heap buffer when a user pastes server-offered clipboard file contents.

FreeRDP before 3.29.0 contains integer overflow vulnerabilities in the audio input redirection channel (audin) across ALSA, sndio, WinMM, and OpenSL ES backends that fail to validate the FramesPerPacket parameter from RDP servers. Attackers can supply a malicious FramesPerPacket value causing allocation size wraparound, resulting in heap-based buffer overflow on ALSA or denial of service on all platforms.

FreeRDP before 3.29.0 (affected versions <= 3.28.0) contains a divide-by-zero vulnerability in the rdpecam camera redirection client. ecam_dev_process_start_streams_request() parses a server-controlled CAM_MEDIA_TYPE_DESCRIPTION from a StartStreamsRequest PDU but validates only Format and Flags, not FrameRateDenominator. When a malicious or compromised RDP server sends a StartStreamsRequest with FrameRateDenominator set to zero, ecam_encoder_context_init() (channels/rdpecam/client/encoding.c) computes FrameRateNumerator / FrameRateDenominator, causing an integer division by zero (SIGFPE) and termination of the FreeRDP client process. Camera redirection must be enabled on the client for the channel to be reachable. Fixed in FreeRDP 3.29.0.

FreeRDP before 3.29.0 contains a null pointer dereference vulnerability in smartcard device control request cleanup when reader-state decoding fails. Attackers can send malformed smartcard IRP requests with non-zero cReaders and truncated reader-state data to crash the process via null pointer access in free_reader_states functions.