FreeRDP is a set of free and open source remote desktop protocol library and clients. In affected versions an integer overflow in freerdpbitmapplanarcontextreset leads to heap-buffer overflow. This affects FreeRDP based clients. FreeRDP based server implementations and proxy are not affected. A malicious server could prepare a RDPGFXRESETGRAPHICSPDU to allocate too small buffers, possibly triggering later out of bound read/write. Data extraction over network is not possible, the buffers are used to display an image. This issue has been addressed in version 2.11.5 and 3.2.0. Users are advised to upgrade. there are no know workarounds for this vulnerability.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.20.1, a heap use-after-free occurs in irpthreadfunc because the IRP is freed by irp->Complete() and then accessed again on the error path. This vulnerability is fixed in 3.20.1.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, xfAppUpdateWindowFromSurface reuses a cached XImage whose data pointer references a freed RDPGFX surface buffer, because gdiDeleteSurface frees surface->data without invalidating the appWindow->image that aliases it. Version 3.23.0 fixes the issue.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, xfAppUpdateWindowFromSurface reads from a freed xfAppWindow because the RDPGFX DVC thread obtains a bare pointer via xfrailgetwindow without any lifetime protection, while the main thread can concurrently delete the window through a fastpath window-delete order. Version 3.23.0 fixes the issue.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, xfcliprdrprovidedata passes freed pDstData to XChangeProperty because the cliprdr channel thread calls xfcliprdrserverformatdataresponse which converts and uses the clipboard data without holding any lock, while the X11 event thread concurrently calls xfcliprdrclearcacheddata → HashTableClear which frees the same data via xfcacheddatafree, triggering a heap use after free. Version 3.23.0 fixes the issue.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.24.0, a sizet underflow in the IMA-ADPCM and MS-ADPCM audio decoders leads to heap-buffer-overflow write via the RDPSND audio channel. In libfreerdp/codec/dsp.c, the IMA-ADPCM and MS-ADPCM decoders subtract block header sizes from a sizet variable without checking for underflow. When nBlockAlign (received from the server) is set such that size % blocksize == 0 triggers the header parsing at a point where size is smaller than the header (4 or 8 bytes), the subtraction wraps size to ~SIZEMAX. The while (size > 0) loop then continues for an astronomical number of iterations. This vulnerability is fixed in 3.24.0.

FreeRDP prior to version 2.0.0-rc4 contains an Integer Truncation that leads to a Heap-Based Buffer Overflow in function updatereadbitmapupdate() and results in a memory corruption and probably even a remote code execution.

FreeRDP prior to version 2.0.0-rc4 contains a Heap-Based Buffer Overflow in function zgfxdecompress() that results in a memory corruption and probably even a remote code execution.

FreeRDP prior to version 2.0.0-rc4 contains a Heap-Based Buffer Overflow in function zgfxdecompresssegment() that results in a memory corruption and probably even a remote code execution.

In FreeRDP before 2.4.0 on Windows, wfcliprdrserverfilecontentsrequest in client/Windows/wfcliprdr.c has missing input checks for a FILECONTENTSRANGE File Contents Request PDU.

In FreeRDP before 2.4.0 on Windows, wfcliprdrserverfilecontentsrequest in client/Windows/wfcliprdr.c has missing input checks for a FILECONTENTSSIZE File Contents Request PDU.

FreeRDP prior to version 2.0.0-rc4 contains an Integer Overflow that leads to a Heap-Based Buffer Overflow in function gdiBitmapDecompress() and results in a memory corruption and probably even a remote code execution.

FreeRDP prior to version 2.0.0-rc4 contains an Out-Of-Bounds Write of up to 4 bytes in function nscrledecode() that results in a memory corruption and possibly even a remote code execution.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.24.0, there is an out-of-bounds read in MS-ADPCM and IMA-ADPCM decoders due to unchecked predictor and stepindex values from input data. This vulnerability is fixed in 3.24.0.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.24.0, the gdisurfacebits() function processes SURFACEBITSCOMMAND messages sent by the RDP server. When the command is handled using NSCodec, the bmp.width and bmp.height values provided by the server are not properly validated against the actual desktop dimensions. A malicious RDP server can supply crafted bmp.width and bmp.height values that exceed the expected surface size. Because these values are used during bitmap decoding and memory operations without proper bounds checking, this can lead to a heap buffer overflow. Since the attacker can also control the associated pixel data transmitted by the server, the overflow may be exploitable to overwrite adjacent heap memory. This vulnerability is fixed in 3.24.0.

FreeRDP before 3.28.0 (affected <=3.27.1) contains a heap-based buffer overflow in cryptorsacommon() (libfreerdp/crypto/crypto.c). The function writes the modular-exponentiation result into the caller's output buffer via BNbn2bin() and only afterward checks outputlength > outlength, so out-of-bounds bytes are written before the bounds check. On the server side, when a client selects RDP Standard Security, the encrypted client random is decrypted into a fixed 32-byte buffer. Because the server publishes its RSA public key, an unauthenticated attacker can forge a ciphertext whose decrypted value is up to the full modulus length (e.g. 256 bytes for RSA-2048), overflowing the 32-byte heap buffer by up to ~224 attacker-controlled bytes pre-authentication, resulting in denial of service.

FreeRDP before 3.28.0 (affected 3.x through 3.27.1) contains a double-free vulnerability in freerdpclientrdpfileapplytosettings() (client/common/file.c) when parsing the selectedmonitors field of a .rdp connection file. The MonitorIds array is allocated through the settings object, and a raw non-owning pointer to it is freed on the strtoul error path without clearing settings->MonitorIds, leaving it dangling; at teardown freerdpsettingsfree() frees the same buffer again. An attacker who convinces a victim to open a crafted .rdp file with oversized monitor tokens can trigger a size-controlled double-free in any FreeRDP CLI client (xfreerdp/sdl-freerdp/wlfreerdp) in the default configuration.

FreeRDP before 3.29.0 contains a buffer over-disclosure vulnerability in the gateway WebSocket transport (libfreerdp/core/gateway/websocket.c). The client's Pong reply reuses a fixed 1024-byte response stream whose length is not sealed to the actual received Ping payload, so a malicious gateway/WebSocket peer sending a non-empty Ping control frame causes the client to reply with an overlong Pong that discloses bytes beyond the received payload (the peer receives the masking key and can unmask the reply). A zero-length Ping reaches an assertion and terminates the client (denial of service).

FreeRDP before 3.29.0 improperly validates the Extended Key Usage (EKU) purpose of the peer certificate during client-side server TLS authentication. In x509utilsverify(), when server-purpose (X509PURPOSESSLSERVER) verification fails, the code falls back to client-purpose and any-purpose verification, so a trusted, hostname-matching certificate valid only for clientAuth can be accepted as the RDP server certificate. In environments relying on EKU separation between client and server certificates, this allows a clientAuth-only certificate issued by a trusted CA to bypass server certificate purpose validation.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.20.0, a vulnerability exists in FreeRDP’s certificate handling code on Windows platforms. The function freerdpcertificatedatahash uses the Microsoft-specific snprintf function to format certificate cache filenames without guaranteeing NUL termination when truncation occurs. According to Microsoft documentation, snprintf does not append a terminating NUL byte if the formatted output exceeds the destination buffer size. If an attacker controls the hostname value (for example via server redirection or a crafted .rdp file), the resulting filename buffer may not be NUL-terminated. Subsequent string operations performed on this buffer may read beyond the allocated memory region, resulting in a heap-based out-of-bounds read. In default configurations, the connection is typically terminated before sensitive data can be meaningfully exposed, but unintended memory read or a client crash may still occur under certain conditions. Version 3.20.0 has a patch for the issue.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.22.0, ecamencodercompressh264 trusts server-controlled dimensions and does not validate the source buffer size, leading to an out-of-bounds read in swsscale. This vulnerability is fixed in 3.22.0.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.24.0, there is an out-of-bounds read in freerdpbitmapdecompressplanar when SrcSize is 0. The function dereferences srcp (which points to pSrcData) without first verifying that SrcSize >= 1. When SrcSize is 0 and pSrcData is non-NULL, this reads one byte past the end of the source buffer. This vulnerability is fixed in 3.24.0.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, in the RLE planar decode path, planardecompressplanerle() writes into pDstData at ((nYDst+y) nDstStep) + (4nXDst) + nChannel without verifying that (nYDst+nSrcHeight) fits in the destination height or that (nXDst+nSrcWidth) fits in the destination stride. When TempFormat != DstFormat, pDstData becomes planar->pTempData (sized for the desktop), while nYDst is only validated against the surface by iswithinsurface(). A malicious RDP server can exploit this to perform a heap out-of-bounds write with attacker-controlled offset and pixel data on any connecting FreeRDP client. The OOB write reaches up to 132,096 bytes past the temp buffer end, and on the brk heap (desktop ≤ 128×128), an adjacent NSCCONTEXT struct's decode function pointer is overwritten with attacker-controlled pixel data — control-flow–relevant corruption (function pointer overwritten) demonstrated under deterministic heap layout (nsc->decode = 0xFF414141FF414141). Version 3.23.0 fixes the vulnerability.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, a malicious RDP server can trigger a heap buffer overflow in FreeRDP clients using the GDI surface pipeline (e.g., xfreerdp) by sending an RDPGFX ClearCodec surface command with an out-of-bounds destination rectangle. The gdiSurfaceCommandClearCodec() handler does not call iswithinsurface() to validate the command rectangle against the destination surface dimensions, allowing attacker-controlled cmd->left/cmd->top (and subcodec rectangle offsets) to reach image copy routines that write into surface->data without bounds enforcement. The OOB write corrupts an adjacent gdiGfxSurface struct's codecs pointer with attacker-controlled pixel data, and corruption of codecs is sufficient to reach an indirect function pointer call (NSCCONTEXT.decode at nsc.c:500) on a subsequent codec command — full instruction pointer (RIP) control demonstrated in exploitability harness. Users should upgrade to version 3.23.0 to receive a patch.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP server can trigger a heap-buffer-overflow write in the FreeRDP client by sending crafted RDPGFX PDUs. The bug is in gdiCacheToSurface: it validates a destination rectangle that is clamped to UINT16MAX, but then performs the copy using the original cacheEntry->width/height. This can cause a large out-of-bounds heap write and may lead to client crashes or code execution. This bug is reachable from a malicious RDP server, but only when the client has RDPGFX enabled. This vulnerability is fixed in 3.26.0.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP client can trigger a heap-buffer-overflow write in FreeRDP's server-side clipboard (cliprdr) channel by sending a CBCLIPCAPS PDU with a too-small capabilitySetLength. This can crash the server process (remote DoS) and may be exploitable for code execution because it corrupts heap memory. This vulnerability is fixed in 3.26.0.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, FreeRDP's RDPEAR NDR parser accepts one non-null NDR pointer ref-id for multiple logical pointer fields without tracking the pointed object's expected NDR type or ownership. When the same ref-id is reused across two pointer fields, the parser assigns the same heap object to both output fields. The generic destructor later walks each field independently and destroys/frees both pointers. This causes a malicious-server-triggerable heap use-after-free / double-free in the FreeRDP client's RDPEAR authentication-redirection path. This vulnerability is fixed in 3.26.0.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.1, FreeRDP clients launched with the non-default /cache:codec:rfx option pass desktop stride and height to RemoteFX decoding for Cache Bitmap V3 data while allocating bitmap->data only for the smaller DstWidth and DstHeight in gdiBitmapDecompress, allowing a malicious RDP server to trigger a heap out-of-bounds write with attacker-controlled offset and content. This issue is fixed in version 3.27.1.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.22.0, the RDPSND async playback thread can process queued PDUs after the channel is closed and internal state is freed, leading to a use after free in rdpsndtreatwave. This vulnerability is fixed in 3.22.0.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.22.0, The URBDRC client uses server-supplied interface numbers as array indices without bounds checks, causing an out-of-bounds read in libusbudevselectinterface. This vulnerability is fixed in 3.22.0.