Vulnerability · Published Feb 25, 2026 · Assigned by GitHub_M
CVE-2026-27015FreeRDP: Smartcard NDR Alignment Padding Triggers Reachable WINPR_ASSERT Abort (Client DoS)
Medium 5.0
In plain English
A medium-severity security flaw in FreeRDP from FreeRDP. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 24% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, a missing bounds check in `smartcard_unpack_read_size_align()` (`libfreerdp/utils/smartcard_pack.c:1703`) allows a malicious RDP server to crash the FreeRDP client via a reachable `WINPR_ASSERT` → `abort()`. The crash occurs in upstream builds where `WITH_VERBOSE_WINPR_ASSERT=ON` (default in FreeRDP 3.22.0 / current WinPR CMake defaults). Smartcard redirection must be explicitly enabled by the user (e.g., `xfreerdp /smartcard`; `/smartcard-logon` implies `/smartcard`). Version 3.23.0 fixes the issue.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | freerdp2 | no fix listed | DEBIAN-CVE-2026-27015 |
| Debian:13 | freerdp3 | 3.15.0+dfsg-2.1+deb13u1 | DEBIAN-CVE-2026-27015 |
| Debian:14 | freerdp3 | 3.23.0+dfsg-1 | DEBIAN-CVE-2026-27015 |
| Ubuntu:22.04:LTS | freerdp2 | no fix listed | UBUNTU-CVE-2026-27015 |
| Ubuntu:24.04:LTS | freerdp3 | 3.5.1+dfsg1-0ubuntu1.4 | USN-8105-1 |
| Ubuntu:24.04:LTS | freerdp3 | 3.5.1+dfsg1-0ubuntu1.4 | UBUNTU-CVE-2026-27015 |
| Ubuntu:25.10 | freerdp3 | 3.16.0+dfsg-2ubuntu0.3 | UBUNTU-CVE-2026-27015 |
| Ubuntu:25.10 | freerdp3 | 3.16.0+dfsg-2ubuntu0.3 | USN-8105-1 |
Affected products (as reported)
Weakness: CWE-617 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P