A heap-based buffer overflow was found in the vsysloginternal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when the openlog function was not called, or called with the ident argument set to NULL, and the program name (the basename of argv[0]) is bigger than 1024 bytes, resulting in an application crash or local privilege escalation. This issue affects glibc 2.36 and newer.
An issue was discovered in the GNU C Library (glibc) 2.36. When the syslog function is passed a crafted input string larger than 1024 bytes, it reads uninitialized memory from the heap and prints it to the target log file, potentially revealing a portion of the contents of the heap.