This is a patch release of 4.97 containing fixes for CVE-2023-51766.
ref.:
ref.:
Bug 3063 – "SMTP Smuggling" attack
bugs.exim.org
NVD - CVE-2023-51766
nvd.nist.gov
2255852 – (CVE-2023-51766) CVE-2023-51766 exim: SMTP smuggling vulnerability
bugzilla.redhat.com