An information disclosure vulnerability exists in the /proc/pid/syscall
functionality of Linux Kernel 5.1 Stable and 5.4.66. More specifically,
this issue has been introduced in v5.1-rc4 (commit
631b7abacd02b88f4b0795c08b54ad4fc3e7c7c0) and is still present in
v5.10-rc4, so it’s likely that all versions in between are affected. An
attacker can read /proc/pid/syscall to trigger this vulnerability, which
leads to the kernel leaking memory contents.

It was discovered that an information leak existed in the syscall
implementation in the Linux kernel on 32 bit systems. A local attacker
could use this to expose sensitive information (kernel memory).