Abseil-cpp contains a heap buffer overflow issue. The `sized constructors`, `reserve()`, and `rehash()` methods of `absl::{flat,node}hash{set,map}` did not enforce a limit on the size of their input argument. This allowed a malicious actor to provide a large size, causing an integer overflow when calculating the container's backing store size, leading to an out-of-bounds memory write. Subsequent access to the container could also result in out-of-bounds memory access. The issue could potentially allow an attacker to cause a denial of service or memory corruption.