CVE-2026-22858

MEDIUM EPSS 30.2%
Published Jan 14, 20265mo ago · Modified Jun 17, 20261w ago
5.6 CVSS 4.0
Medium
Find Similar
Published Jan 14, 2026 5mo ago
Last Modified Jun 17, 2026 1w ago

Description

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.

CVSS Details

Base Score
5.6
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction P
Scope X

Threat Intelligence

EPSS Exploit Probability
30.2% percentile
Exploit & Patch Status
Public Exploit Known
No Patch Available

Weaknesses 2

CWE-125 Out-of-bounds Read Memory Safety
CWE-758

Affected Products 1

VendorProductVersionRange
freerdpfreerdp* <3.20.1

References 2

  • github.com https://github.com/FreeRDP/FreeRDP/releases/tag/3.20.1
    Release Notes
  • github.com https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qmqf-m84q-x896
    ExploitVendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.