A xz project repository continues to show changes made by the backdoor author to block protection mechanisms. A change was detected in the CMakeLists.txt assembly script that prevented the use of the Landlock application isolation mechanism when supported by the system. In the C code checking the availability of the Landlock system call, an extra dot was intentionally added, causing the Landlock availability check to fail under all conditions.
The change was added by Jia Tan on February 26 under the guise of implementing an extended check for Landlock support. Previously, the output for Landlock support was determined solely based on the presence of the header file 'linux/landlock.h', but the change included a C-written test that additionally called prctl for verification. Due to the extra dot left at the beginning of the line, this code was non-functional, causing the test to always fail.
Forrás: opennet.ru
