CVE-2021-23017

Описание

A security issue in nginx resolver was identified, which might allow an attacker who is able to forge UDP packets from the DNS server to cause 1-byte memory overwrite, resulting in worker process crash or potential other impact.

A flaw was found in nginx. An off-by-one error while processing DNS responses allows a network attacker to write a dot character out of bounds in a heap allocated buffer which can allow overwriting the least significant byte of next heap chunk metadata likely leading to a remote code execution in certain circumstances. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.