A vulnerability was found in WebAssembly wabt up to 1.0.37 and classified as problematic. This issue affects the function LogOpcode of the file src/binary-reader-objdump.cc. The manipulation leads to reachable assertion. Local access is required to approach this attack. The exploit has been disclosed to the public and may be used. The real existence of this vulnerability is still doubted at the moment. The code maintainer explains that this issue might not affect real world wasm programs.
The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.
While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, it can still lead to a denial of service. For example, if a server handles multiple simultaneous connections, and an assert() occurs in one single connection that causes all other connections to be dropped, this is a reachable assertion that leads to a denial of service.