Versions mentioned in the description apply to the upstream
Remediation section below for
Debian:9 relevant versions.
A flaw was found in the way CHACHA20-POLY1305 was implemented in NSS in versions before 3.55. When using multi-part Chacha20, it could cause out-of-bounds reads. This issue was fixed by explicitly disabling multi-part ChaCha20 (which was not functioning correctly) and strictly enforcing tag length. The highest threat from this vulnerability is to confidentiality and system availability.
nss to version 2:3.26.2-1.1+deb9u2 or higher.