A flaw was found in the way TLS 1.2 could use the MD5 hash function for
signing ServerKeyExchange and Client Authentication packets during a TLS
handshake. A man-in-the-middle attacker able to force a TLS connection to
use the MD5 hash function could use this flaw to conduct collision attacks
to impersonate a TLS server or an authenticated TLS client.
(CVE-2015-7575)
For the update to take effect, all applications linked to the GnuTLS
library must be restarted.
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