Florian Weimer discovered two security problems in the Chrony time synchronisation software (buffer overflows and use of uninitialised data in command replies).
For the oldstable distribution (squeeze), these problems will be fixed soon in 1.24-3+squeeze1 (due to a technical restriction in the archive processing scripts the two updates cannot be released together).
For the stable distribution (wheezy), these problems have been fixed in version 1.24-3.1+deb7u2.
For the unstable distribution (sid), these problems will be fixed soon.
We recommend that you upgrade your chrony packages.