Vulnerability Database

320,453

Total vulnerabilities in the database

CVE-2026-22858

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.20.1, global-buffer-overflow was observed in FreeRDP's Base64 decoding path. The root cause appears to be implementation-defined char signedness: on Arm/AArch64 builds, plain char is treated as unsigned, so the guard c <= 0 can be optimized into a simple c != 0 check. As a result, non-ASCII bytes (e.g., 0x80-0xFF) may bypass the intended range restriction and be used as an index into a global lookup table, causing out-of-bounds access. This vulnerability is fixed in 3.20.1.

  • Published: Jan 14, 2026
  • Updated: Jan 21, 2026
  • CVE: CVE-2026-22858
  • Severity: Critical
  • Exploit:

CVSS v3:

  • Severity: Critical
  • Score: 9.1
  • AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H