Freerdp vulnerabilities

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 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 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 that allows a malicious RD Gateway to crash clients by sending mismatched message lengths. Attackers controlling the 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 disrupt client availability.

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

FreeRDP from 3.0.0 before 3.32.0 contains an uninitialized memory disclosure vulnerability in smartcard_Transmit_Call that allows malicious RDP servers to read client memory. Servers 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 that allows malicious RDP servers to exhaust client memory via oversized drive redirection read requests. Attackers 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 before 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.