Vulnerability · Published Aug 1, 2026 · Assigned by VulnCheck
CVE-2026-67306FreeRDP before 3.29.0 Out-of-Bounds Read via Planar RLE
Medium 5.4
In plain English
A medium-severity out-of-bounds read in FreeRDP from FreeRDP. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 32% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | freerdp2 | no fix listed | DEBIAN-CVE-2026-67306 |
| Debian:13 | freerdp3 | no fix listed | DEBIAN-CVE-2026-67306 |
| Debian:14 | freerdp3 | 3.29.0+dfsg-1 | DEBIAN-CVE-2026-67306 |
| Ubuntu:22.04:LTS | freerdp2 | no fix listed | UBUNTU-CVE-2026-67306 |
| Ubuntu:24.04:LTS | freerdp3 | 3.30.0+dfsg-0ubuntu0.24.04.1 | UBUNTU-CVE-2026-67306 |
| Ubuntu:26.04:LTS | freerdp3 | 3.30.0+dfsg-0ubuntu0.26.04.1 | UBUNTU-CVE-2026-67306 |
Affected products (as reported)
Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L
References
- GitHub Security Advisory (GHSA-qrxx-7g3c-j6w3) vendor-advisory
- Patch Commit patch
- VulnCheck Advisory: FreeRDP before 3.29.0 Out-of-Bounds Read via Planar RLE third-party-advisory