An issue was discovered in klibc before 2.0.9. Additions in the malloc() function may result in an integer overflow and a subsequent heap buffer overflow.
https://lists.zytor.com/archives/klibc/2021-April/004593.html
https://lists.debian.org/debian-lts-announce/2021/06/msg00025.html
https://kernel.org/pub/linux/libs/klibc/2.0/
https://github.com/huolinjue/klibc/commit/a31ae8c508fc8d1bca4f57e9f9f88127572d5202