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FreeBSD Alpha Port Lack Of /dev/random and /dev/urandom Vulnerability
Solution: OpenSSL 0.9.5 added checks to make sure the calls that use (open, read from, etc) the devices work. FreeBSD corrected the following distributions for the Alpha platform on the dates listed below: 2000-05-10 (4.0-STABLE) 2000-04-28 (5.0-CURRENT) If you are using a FreeBSD distribution of these versions obtained earlier than the dates shown, you can take the following steps (copied from the advisory): 1a) Upgrade your FreeBSD/Alpha system to FreeBSD 4.0-STABLE after the correction date. 1b) install the patched 4.0-RELEASE GENERIC kernel available from: ftp://ftp.freebsd.org/pub/FreeBSD/CERT/patches/SA-00:25/kernel.gz e.g. perform the following steps as root: # fetch ftp://ftp.freebsd.org/pub/FreeBSD/CERT/patches/SA-00:25/kernel.gz # fetch ftp://ftp.freebsd.org/pub/FreeBSD/CERT/patches/SA-00:25/kernel.gz.asc [ Verify the detached PGP signature using your PGP utility - consult your utility's documentation for how to do this ] # gunzip kernel.gz # cp /kernel /kernel.old # chflags noschg /kernel # cp kernel /kernel # chflags schg /kernel 1c) Download the kernel source patch and rebuild your FreeBSD/Alpha kernel, as follows: # fetch ftp://ftp.freebsd.org/pub/FreeBSD/CERT/patches/SA-00:25/kernel.sys.diff Download the detached PGP signature: # fetch ftp://ftp.freebsd.org/pub/FreeBSD/CERT/patches/SA-00:25/kernel.sys.diff.asc and verify the signature using your PGP utility. Apply the patch: # cd /usr/src # patch -p < /path/to/kernel.sys.diff Rebuild your kernel as described in http://www.freebsd.org/handbook/kernelconfig.html and reboot with the new kernel. NOTE: Because of the significant improvements to the FreeBSD/Alpha platform in FreeBSD 4.0, it is not planned at this time to backport the necessary changes to FreeBSD 3.4-STABLE. 2) Immediately regenerate all OpenSSH-generated SSH keys and OpenSSL-generated SSL certificates, and any other data relying on cryptographic random numbers which were generated on FreeBSD/Alpha systems, whose strength cannot be verified. [Note: for most systems, the only significant vulnerability is likely to be from OpenSSH and OpenSSL-generated keys and certificates (e.g. for SSL webservers)] |
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