Out-of-bounds Read in Freerdp

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 planar_decompress_plane_rle and planar_decompress_plane_rle_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.

Vulnerability class: Buffer Overflow

EPSS: 0.003 (20.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-67306?
CVE-2026-67306 is a medium-severity vulnerability in Freerdp, classified under Out-of-bounds Read. CVSS score: 5.4/10. Published 2026-08-01.
How severe is CVE-2026-67306?
Medium severity. CVSS v3 base score is 5.4 out of 10.