Security Information / 2017 / Security Information -- DSA-3912-1 heimdal

Debian Security Advisory

DSA-3912-1 heimdal -- security update

Date Reported:

16 Jul 2017

Affected Packages:

heimdal

Vulnerable:

Yes

Security database references:

In the Debian bugtracking system: Bug 868208.
In Mitre's CVE dictionary: CVE-2017-11103.

More information:

Jeffrey Altman, Viktor Dukhovni, and Nicolas Williams reported that Heimdal, an implementation of Kerberos 5 that aims to be compatible with MIT Kerberos, trusts metadata taken from the unauthenticated plaintext (Ticket), rather than the authenticated and encrypted KDC response. A man-in-the-middle attacker can use this flaw to impersonate services to the client.

See https://orpheus-lyre.info/ for details.

For the oldstable distribution (jessie), this problem has been fixed in version 1.6~rc2+dfsg-9+deb8u1.

For the stable distribution (stretch), this problem has been fixed in version 7.1.0+dfsg-13+deb9u1.

For the unstable distribution (sid), this problem has been fixed in version 7.4.0.dfsg.1-1.

We recommend that you upgrade your heimdal packages.