Debian DSA-3588-1 Critical: Symfony SecureRandom and Session Issues

CVE-2016-1902

Lander Brandt discovered that the class SecureRandom might generate
weak random numbers for cryptographic use under certain settings. If
the functions random_bytes() or openssl_random_pseudo_bytes() are not
available, the output of SecureRandom should not be consider secure.

CVE-2016-4423

Marek Alaksa from Citadelo discovered that it is possible to fill up
the session storage space by submitting inexistent large usernames.

For the stable distribution (jessie), these problems have been fixed in
version 2.3.21+dfsg-4+deb8u3.

For the testing distribution (stretch), these problems have been fixed
in version 2.8.6+dfsg-1.

For the unstable distribution (sid), these problems have been fixed in
version 2.8.6+dfsg-1.

We recommend that you upgrade your symfony 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/