Debian: DSA 1189-1 Critical: OpenSSH Denial of Service Threat

Tavis Ormandy of the Google Security Team discovered a denial of
service vulnerability in the mitigation code against complexity
attacks, which might lead to increased CPU consumption until a
timeout is triggered. This is only exploitable if support for
SSH protocol version 1 is enabled.

CVE-2006-5051

Mark Dowd discovered that insecure signal handler usage could
potentially lead to execution of arbitrary code through a double
free. The Debian Security Team doesn't believe the general openssh
package without Kerberos support to be exploitable by this issue.
However, due to the complexity of the underlying code we will
issue an update to rule out all eventualities.

For the stable distribution (sarge) these problems have been fixed in
version 3.8.1p1-7sarge1.

For the unstable distribution (sid) these problems have been fixed in
version 4.3p2-4 of openssh. openssh-krb5 will soon be converted towards
a transitional package against openssh.

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