since 1.24 see file NEWS in the distfile.
Security fixes since 1.24:
* Fix crash when processing crafted commands (CVE-2012-4502)
(possible with IP addresses allowed by cmdallow and localhost)
* Don't send uninitialized data in SUBNETS_ACCESSED and CLIENT_ACCESSES
replies (CVE-2012-4503) (not used by chronyc)
Reviewed by: Joerg Sonnenberger <joerg@netbsd.org>