CVE-2020-13397: 
NixOS vulnerability analysis and mitigation

An out-of-bounds (OOB) read vulnerability was discovered in FreeRDP before version 2.1.1, identified as CVE-2020-13397. The vulnerability was detected in the security_fips_decrypt function within libfreerdp/core/security.c, caused by an uninitialized value. This security issue was disclosed on May 22, 2020, affecting FreeRDP implementations across various operating systems (CVE Details, Ubuntu Security).

The vulnerability exists in the security_fips_decrypt function within libfreerdp/core/security.c where an uninitialized value leads to an out-of-bounds read condition. The issue was addressed by adding proper NULL pointer validation checks to prevent accessing uninitialized values. The fix was implemented in commit d6cd14059b257318f176c0ba3ee0a348826a9ef8. The vulnerability has a CVSS 3.1 base score of 5.5 (Medium), with attack vector being Local, attack complexity Low, and privileges required Low (Ubuntu Security).

The vulnerability could allow an attacker to read data outside the intended boundaries of allocated memory due to the uninitialized value in the security_fips_decrypt function. This could potentially lead to information disclosure or client crashes (Debian Security).

The vulnerability requires local access and low privileges to exploit. The attack complexity is rated as low, indicating that the vulnerability is relatively straightforward to exploit under the right conditions. No public exploits were identified in the wild (Ubuntu Security).

The vulnerability was fixed in FreeRDP version 2.1.1. Various Linux distributions have released security updates to address this issue: Ubuntu provided fixes in versions 2.1.1+dfsg1-0ubuntu0.20.04.1 for 20.04 LTS, Debian released fixes in version 2.3.0+dfsg1-2+deb11u1 for bullseye, and OpenSUSE issued the security update openSUSE-SU-2020:1090-1 (Ubuntu Security, OpenSUSE Security).