FreeRDP vulnerabilities

FreeRDP from 3.30.0 before 3.32.0 contains a resource exhaustion vulnerability in the rdpecam client. A malicious RDP server can request unadvertised camera media types by sending a StartStreamsRequest with oversized dimensions, forcing large allocations and reconfiguring the local camera via the HAL.

FreeRDP before 3.32.0 contains a NULL pointer dereference vulnerability in the websocket transport. A malicious gateway can send zero-length pings, causing a nullptr stream to be passed to websocket_reply_close and crashing the client.

FreeRDP 3.3.0 before 3.32.0, when built with WINPR_UTILS_IMAGE_JPEG=ON, has a heap-based out-of-bounds write in winpr_convert_from_jpeg because grayscale JPEG buffers are sized from one input component rather than three BGR output components. A malicious RDP server can offer a grayscale JPEG via clipboard redirection, corrupting client memory and crashing it when the item is pasted as CF_DIB bitmap data.

FreeRDP shadow server from 3.0.0 before 3.32.0 dispatches input PDUs during the Confirm Active state before authentication, allowing unauthenticated attackers to inject keyboard input. Attackers can negotiate TLS-only RDP and send an input PDU without Confirm Active to inject synthetic keystrokes into the host user's X11 session via XTEST.

FreeRDP 2.0.0 before 3.32.0, when built with WITH_LAME=ON and WITH_DSP_FFMPEG=OFF, has a heap-based buffer overflow in freerdp_dsp_decode_mp3 because the right-channel PCM pointer is offset by a byte count treated as short elements. A malicious RDP server can send MP3 audio over rdpsnd so decoded samples cross the heap allocation, crashing the client.

FreeRDP from 3.0.0 before 3.32.0 contains an infinite loop vulnerability in http_response_recv() that allows malicious gateways to exhaust client CPU via crafted Content-Type headers. Attackers controlling a gateway can return a nonzero Content-Length with a semicolon-containing unrecognized Content-Type, pinning a client thread at full CPU indefinitely.

FreeRDP 3.0.0 before 3.32.0 allows HTTP header injection in its proxy because a lone LF in the target portion of a routing token (Cookie: msts=) is not rejected and is written by http_proxy_connect into the CONNECT request line and Host header. A remote unauthenticated RDP client connecting to a proxy using FixedTarget=false and an upstream HTTP proxy can alter HTTP request/header framing at that upstream proxy.

FreeRDP from 2.0.0 before 3.32.0 contains a null pointer dereference vulnerability that allows malicious RDP servers to crash clients by sending out-of-lifecycle serial IRPs. Attackers can send IRP_MJ_READ or IRP_MJ_WRITE before create or after close, causing CommReadFile or CommWriteFile to dereference a null handle and terminate clients using Linux serial redirection.

FreeRDP from 3.0.0-beta1 before 3.32.0 fails to enforce cumulative or absolute size limits when reassembling RDPDR channel fragments in the proxy. Attackers can send a FIRST fragment followed by continuation fragments without LAST, growing per-session heap streams proportional to traffic and exhausting proxy memory.

FreeRDP from 2.0.0 before 3.32.0 contains a memory exhaustion vulnerability in wts_read_drdynvc_data_first that allows authenticated clients to force servers to commit large memory allocations. Attackers can send a seven-byte DATA_FIRST message on an opened DVC declaring a large 32-bit length, causing zeroed resident memory growth and server resource exhaustion.

FreeRDP versions 3.13.0 before 3.32.0 contain a resource retention flaw in drive_process_irp_create, which registers an opened local file in the drive dictionary before applying the allocation size and does not remove it when that operation fails. A malicious RDP server connected to a client with drive redirection enabled can send IRP_MJ_CREATE with AllocationSize set to UINT64_MAX, forcing the seek to fail and leaking the file object and operating-system handle until drive teardown.

FreeRDP before 3.32.0 fails to close prior serial handles in serial_process_irp_create, allowing a malicious RDP server to exhaust file descriptors. Attackers can send repeated serial IRP_MJ_CREATE requests to accumulate descriptors and terminate the client at the CommReadFile FD_SETSIZE assertion.

FreeRDP versions from 3.0.0 before 3.32.0 contain a null pointer dereference in the rdpsnd channel when a fragment sets CHANNEL_FLAG_LAST without CHANNEL_FLAG_FIRST. A malicious RDP server can send a malformed rdpsnd PDU on a fresh channel to crash the client and cause denial of service.

FreeRDP 3.0.0 before 3.32.0 contains an insufficiently protected credentials vulnerability where the /restricted-admin option fails to suppress CredSSP credential delegation, sending the cleartext password to the RDP server. A compromised or man-in-the-middle destination host can decode TSPasswordCreds and the Client Info PDU to obtain reusable administrative domain, username, and password values.

The FreeRDP client 3.0.0 before 3.32.0 does not check a server-selected PROTOCOL_RDSTLS or PROTOCOL_HYBRID_EX against its enabled protocol set in nego_process_negotiation_response(), allowing a security protocol downgrade. A malicious server or man-in-the-middle can select RDSTLS to override /sec:nla pinning, complete authentication with an all-zero cookie, and receive the user's cleartext password in the Client Info PDU.

FreeRDP 3.17.1 before 3.32.0 contains a heap buffer over-read vulnerability in DynvcTrackerHandleCreateBack of the freerdp-proxy DRDYNVC channel handler that allows malicious backend RDP servers to read heap memory out of bounds. Attackers can send a CREATE_REQUEST_PDU whose channel name lacks a NUL byte, causing an unbounded snprintf read that leaks memory into proxy logs or crashes the process.

FreeRDP from 3.0.0 before 3.32.0 contains a heap out-of-bounds read vulnerability. A malicious RD Gateway can set MsgBytes far larger than the NDR string ActualCount in consent or service messages, causing UTF-8 conversion to read past the stream allocation and crash the client.

FreeRDP 3.0.0 before 3.32.0 contains an improper restriction of excessive authentication attempts in its virtual smartcard GIDS implementation, where the PIN retry counter is stored per-handle. A malicious RDP server can exhaust the counter with VERIFY APDUs, then reset attempts via a new SCardConnect, enabling unbounded online brute-forcing of the smartcard PIN.

FreeRDP from 3.0.0 before 3.32.0 contains an uninitialized memory disclosure vulnerability in smartcard_Transmit_Call. A malicious RDP server can send SCardTransmit requests with an invalid card handle and nonzero receive length, causing smartcard_pack_transmit_return to serialize up to 66,560 uninitialized heap bytes.

FreeRDP from 3.20.1 before 3.32.0 contains an uncontrolled resource allocation vulnerability. A malicious RDP server can send IRP_MJ_READ with Length 0xffffffff, causing roughly 4 GiB of zeroed allocation on 64-bit builds or an under-reserved buffer on 32-bit builds.

FreeRDP 3.11.0 before 3.32.0 does not validate that AVC444 and AVC444v2 region widths are even before YUV444 conversion, so an odd width reaches an assertion and aborts the client. A malicious or compromised RDP server can terminate a connected FreeRDP client after RDPGFX AVC444 negotiation by sending an in-bounds region rectangle with an odd width.

FreeRDP 3.0.0 before 3.32.0 contains a heap use-after-free vulnerability in smartcard emulation when SCARD_IOCTL_DISCONNECT and SCARD_IOCTL_TRANSMIT operate concurrently on one card handle. A malicious RDP server can overlap these IRPs through separate context workers to free and reuse the SCardHandle, causing client-process heap corruption and termination.

FreeRDP 3.0.0 before 3.32.0 does not remove card handles when Emulate_SCardReleaseContext releases a smartcard-emulation context, so Emulate_SCardTransmit later looks up the deleted parent context and reaches a terminating WINPR_ASSERT. A malicious RDP server can crash a connecting client with smartcard emulation and redirection enabled by releasing a context, establishing another, and issuing SCardTransmit with the stale card handle.

FreeRDP 3.29.0 before 3.32.0 contains a double free in the client's async-update message proxy, which shallow-copies the parser-owned PolygonSC or PolygonCB points array when numPoints is zero, so both the queue consumer and parser cleanup free it. A malicious RDP server can send a point-bearing polygon order followed by a zero-point order to crash a client with +async-update enabled.

FreeRDP 2.3.0 before 3.32.0 dereferences a NULL stream in rdg_process_close_packet in libfreerdp/core/gateway/rdg.c because rdg_process_control_packet accepts a header-only PKT_TYPE_CLOSE_CHANNEL packet and passes the null payload without a check. A malicious or compromised RD Gateway can send an eight-byte CLOSE_CHANNEL header to crash a connecting FreeRDP client.

FreeRDP from 2.3.0 before 3.32.0 contains an infinite loop vulnerability in http_chuncked_read that allows malicious RD Gateways to hang clients by sending incomplete chunked responses. Attackers can send a partial chunk-size line or footer followed by a clean TLS shutdown, causing zero-byte reads to loop forever and freeze the client decoder thread.

FreeRDP 3.0.0-beta1 through 3.32.0 on Unix builds with PKCS#11 support has a stack-based buffer overflow in wprintKeyName() in WinPR's NCrypt PKCS#11 provider. It hex-encodes a key's CKA_ID, which can be up to 64 bytes, into a fixed 128-byte stack buffer. An attacker supplying a malicious PKCS#11 token or module whose key and matching certificate use a 55- to 64-byte CKA_ID can overflow the client's stack during key enumeration, causing a crash.

FreeRDP 3.27.1 through 3.32.0 contains a NULL pointer dereference in update_read_cache_bitmap_v3_order() in libfreerdp/core/orders.c, which accesses the client bitmap cache when the CBR3_DO_NOT_CACHE flag is set, even though the cache is not yet initialized before Demand Active. A malicious or compromised RDP server can send a Cache Bitmap V3 order during connection setup to crash a connecting client that has enabled the non-default Bitmap Cache V3 feature (/cache:codec:<rfx|nsc|jpeg>).

Positive mapped-video coordinates overflow and abort FreeRDP clients. A malicious or compromised RDP server can terminate a FreeRDP client after the user connects with video redirection enabled.

FreeRDP 3.18.0 through 3.32.0 has a heap-based out-of-bounds write in freerdp_interruptible_get_line, which shrinks the buffer to 32 bytes while keeping a pre-filled suggested username's length as its write offset. A malicious or compromised ARM routing service can return a long redirectedUsername that reaches the CLI credential prompt, crashing the client when the user types input.

FreeRDP 3.0.0-beta4 through 3.32.0 contains a NULL pointer dereference in arm_handle_request_ok when an ARM endpoint returns an empty HTTP 200 body. Attackers controlling the configured ARM gateway can return a zero-length body to pass NULL to strnlen and crash the connecting client.

FreeRDP 3.0.0-beta1 through 3.32.0, when built with verbose WinPR assertions and using smartcard emulation, has a reachable assertion: the emulated SCardStatusA passes a NULL reader-name destination to scard_copy_strings. A malicious RDP server can send an SCardStatusA request with fmszReaderNamesIsNULL=1 to abort a connecting client.

FreeRDP from 2.0.0-beta1 before 3.28.0 contains an out-of-bounds read vulnerability in smartcard_LocateCardsByATRA_Call because the ATR pattern cbAtr byte count is not capped. Malicious RDP servers can send crafted ATR mask arrays to use query timing as an oracle, leaking heap memory bit-by-bit to defeat ASLR and aid RCE exploits.

FreeRDP from 3.0.0-beta1 before 3.32.0 contains a use-after-free vulnerability in smartcard handling that allows attackers to access a freed smartcard handle object after an invalid connect operation. Attackers can trigger an invalid smartcard connect operation to cause reuse of the freed handle, leading to memory corruption or crashes.

FreeRDP before 3.32.0 contains a double-free vulnerability in nsc_context_initialize_encode() that leaves dangling plane pointers after a partial buffer growth failure. Attackers using a crafted RDP client can negotiate NSCodec with a large desktop geometry to trigger allocation failure, crashing the server during context teardown.

FreeRDP 3.10.0 through 3.32.2 contains a heap buffer overflow in the WinPR png_write_data callback that writes past the buffer after a realloc failure. A malicious RDP clipboard peer can supply a large CF_DIB image that triggers out-of-bounds memcpy during PNG conversion, causing a client crash.

FreeRDP 3.0.0 before 3.32.0 contains an integer truncation vulnerability in license_check_stream_length that allows a malicious RDP server to trigger a heap buffer overflow on 32-bit clients. Attackers can send a crafted SERVER_LICENSE_REQUEST with a large scopeCount that bypasses length checks, causing out-of-bounds writes leading to denial of service or remote code execution.

FreeRDP 2.1.0 before 3.32.0 contains a use-after-free vulnerability in the static rdpsnd channel disconnect path, which frees audio formats and device without joining play_thread. A malicious RDP server can disconnect while asynchronous Wave2 playback processes queued PDUs, causing the client to read freed heap memory and crash.

FreeRDP from 3.9.0 before 3.32.0 contains an out-of-bounds read vulnerability in the RDPEAR NDR scalar readers, which check value length before consuming alignment padding. Malicious or compromised RDP servers can send crafted unaligned RDPEAR payloads, such as CreateApReqAuthenticatorReq messages, to clients using Remote Credential Guard, causing over-reads and potentially crashing the client process.

FreeRDP from 3.9.0 before 3.32.0 contains a NULL pointer dereference vulnerability in the RDPEAR NDR reader that allows malicious servers to crash clients via truncated KERB_RPC_INTERNAL_NAME data. Attackers can send a CreateApReqAuthenticatorReq with NameCount of two or more ending before the Names pointer, causing cleanup to dereference a null base and terminate the client.

FreeRDP before 3.32.0 stores the server-supplied signed MS-RDPEGT geometry origin unchecked in an unsigned video surface coordinate, so the blit clamp in gdiVideoShowSurface() wraps in 32-bit arithmetic and is skipped. A malicious RDP server can send a negative topLevelLeft to clients connecting with /video, causing an out-of-bounds write of decoded H.264 picture data or a client abort.

FreeRDP 3.0.0 before 3.32.0 contains a heap buffer overflow vulnerability in collect_keys() that allows local attackers to write past the fixed 64-entry keys array during PKCS#11 key enumeration. Attackers controlling smartcard tokens can present more than 64 public key objects across multiple slots to corrupt heap memory with attacker-chosen CKA_ID and CKA_LABEL data during smartcard logon.

FreeRDP 3.0.0 before 3.32.0 contains a heap out-of-bounds read in freerdp_assistance_parse_all_elements_of() because it advances its parsing cursor without reducing the remaining length, letting the scan window exceed the decrypted ConnectionString2 buffer. Attackers can supply a crafted .msrcIncident invitation file and password that crash xfreerdp when opened, before any RDP connection.

FreeRDP 3.0.0 before 3.32.0 contains a heap out-of-bounds read in the WinPR clipboard function convert_filedescriptors_to_file_list(), which scans a server-controlled FILEDESCRIPTORW cFileName with unbounded _wcschr() and count_special_chars() calls without a NUL-termination guarantee. A malicious RDP server can send an odd-length FILEDESCRIPTORW blob in a CB_FORMAT_DATA_RESPONSE, crashing X11, Wayland, and SDL clients when the user pastes server-copied files.

FreeRDP before 3.32.0 contains a path traversal vulnerability in convert_filedescriptors_to_file_list() in winpr/libwinpr/clipboard/synthetic_file.c. A malicious RDP server can supply '../' sequences so the user's next clipboard paste copies an arbitrary local file instead of the expected remote file.

FreeRDP before 3.32.0 contains a divide-by-zero vulnerability in the freerdp-shadow-cli shadow server: the frame id in a client's Frame Acknowledge PDU is stored without a range check, so the in-flight frame count in shadow_encoder_inflight_frames() can underflow. An authenticated client can acknowledge a frame id one greater than the last frame sent, causing shadow_encoder_create_frame_id() to divide by zero (SIGFPE) and terminate the process, disconnecting all viewers.

FreeRDP 3.0.0 before 3.32.0 contains an improper certificate validation vulnerability in freerdp_http_request() in libfreerdp/utils/http.c that completes TLS handshakes without verifying the server certificate chain. On-path attackers can impersonate login.microsoftonline.com in the Azure AD authentication flow to capture OAuth authorization codes and substitute the OpenID discovery document.

FreeRDP from 2.0.0 before 3.32.0 contains an insecure permission vulnerability in winpr-makecert that creates unencrypted private keys without owner-only file modes. Local users on multi-user Unix hosts can read world-readable key files or open PFX files protected by the hard-coded default password to steal private keys.

FreeRDP from 3.0.0 before 3.32.0 contains an incorrect permission assignment vulnerability that allows local users to read private keys written by crypto_write_pem without owner-only permissions. Attackers on multi-user Unix hosts can enumerate the shared temporary directory during soft-smartcard logon to read the world-readable PKINIT private-key copy.

FreeRDP before 3.0.0 and 3.6.0 before 3.32.0 renders uninitialized heap memory from un-decoded progressive tiles because the tile->current buffer is allocated without zeroing. A malicious RDP server can send a crafted WBT_TILE_FIRST then WBT_TILE_UPGRADE sequence to paint heap bytes onscreen or abort the client process.