Debian 9 DSA-4567-2 Critical: Flex Buffer Overflow Risk

Alexander Sulfrian discovered a buffer overflow in the
yy_get_next_buffer() function generated by Flex, which may result in
denial of service and potentially the execution of code if operating on
data from untrusted sources.

Affected applications need to be rebuild. bogofilter will be rebuild
against the updated flex in a followup update. Further affected
applications should be reported at the bug referenced above.

For the stable distribution (jessie), this problem has been fixed in
version 2.5.39-8+deb8u1.

For the testing distribution (stretch), this problem has been fixed
in version 2.6.1-1.

For the unstable distribution (sid), this problem has been fixed in
version 2.6.1-1.

We recommend that you upgrade your flex packages.

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://www.debian.org/security/