FreeRDP before 3.29.0 (affected versions <= 3.28.0) contains multiple TLS certificate identity validation weaknesses in tls_verify_certificate(), tls_match_hostname(), and x509_utils_get_dns_names(). Because FreeRDP performs custom Common Name and DNS SAN string matching instead of using OpenSSL's length-aware identity validation APIs, it (1) truncates DNS SAN values at embedded NUL bytes (accepting e.g. 'victim.example\0.attacker.example' as 'victim.example'), (2) accepts a matching Common Name even when non-matching DNS SAN entries are present, and (3) accepts IP-literal targets via DNS/CN matching without comparing iPAddress SANs. Under a trusted or misissued certificate chain, an attacker positioned to present such a certificate can bypass server identity verification, weakening TLS server authentication.
FreeRDP before 3.29.0 contains a null pointer dereference vulnerability in smartcard cache request decoders that accept NULL NDR pointers for LookupName in SCARD_IOCTL_READCACHEA and SCARD_IOCTL_WRITECACHEA operations. When smartcard emulation is enabled, attackers can send crafted smartcard cache requests with NULL lookup-name pointers to trigger strlen() on a null pointer, causing client process termination.
FreeRDP before 3.29.0 (affected versions <= 3.28.0) does not validate CRLF and control characters in the server-controlled RDP redirection TargetNetAddress field. This value is copied into the client's ServerHostname and, when the client connects through an HTTP proxy, is written directly into the proxy CONNECT request line and Host header by http_proxy_connect() without filtering. A malicious or compromised RDP server can send a crafted redirection PDU containing embedded control characters to inject arbitrary headers/requests into the HTTP proxy CONNECT request.
FreeRDP before 3.29.0 contains a heap out-of-bounds read vulnerability in the TSMF FFmpeg decoder when parsing AVC1 MPEG2VIDEOINFO media types with insufficient ExtraData. Attackers can send malformed media format data from a server to trigger a crash by reading fixed offsets without validating source buffer length.
FreeRDP before 3.28.0 treats lines beginning with forward slash in RDP files as raw command-line options, exposing the entire CLI parser surface to untrusted files. Attackers can craft malicious RDP files with /rdp2tcp, /cert:ignore, or /drive options to execute arbitrary commands, bypass certificate validation, or expose local filesystems without user interaction.
FreeRDP before 3.28.0 (affected <=3.27.1) contains a heap-based buffer overflow in crypto_rsa_common() (libfreerdp/crypto/crypto.c). The function writes the modular-exponentiation result into the caller's output buffer via BN_bn2bin() and only afterward checks output_length > out_length, 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 freerdp_client_rdp_file_apply_to_settings() (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 freerdp_settings_free() 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 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 gdi_Bitmap_Decompress, 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 3.28.0 on 32-bit builds, FreeRDP clients contain an integer overflow in update_read_delta_points in libfreerdp/core/orders.c when multiplying an attacker-controlled point count by sizeof(DELTA_POINT), allowing a malicious RDP peer to allocate an undersized heap buffer and then write beyond it during initialization. This issue is fixed in version 3.28.0.
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.28.0, FreeRDP server implementations with the MS-RDPECAM camera device enumerator channel enabled scan attacker-supplied DeviceName and VirtualChannelName fields for a NUL terminator in channels/rdpecam/server/camera_device_enumerator_main.c and then dereference once past the scan bound, allowing a malicious RDP client to trigger a 1- to 2-byte out-of-bounds heap read. This issue is fixed in version 3.28.0.