CVE-2026-67306

FreeRDP versions 3.28.0 and earlier contain an out-of-bounds read vulnerability in the RDP6 planar RLE bitmap decoder functions planardecompressplanerle and planardecompressplanerle_only in libfreerdp/codec/planar.c. Only the 1-byte control byte is bounds-checked; the subsequent 0–15 attacker-declared raw bytes are read without validating that the source buffer contains them. A malicious or compromised RDP server can send a truncated planar-encoded bitmap or surface update (reachable via both the Bitmap Update PDU and RDPGFX Surface Command paths) that causes the client to read past the end of the source buffer. The issue is fixed in FreeRDP 3.29.0.