From $URL : A flaw in how TLS/DTLS, when CBC-mode encryption is used, communicates was reported. This vulnerability can allow for a Man-in-the-Middle attacker to recover plaintext from a TLS/DTLS connection, when CBC-mode encryption is used. This flaw is in the TLS specification, and not a bug in a specific implementation (as such, it affects nearly all implementations). As such, it affects all TLS and DTLS implementations that are compliant with TLS 1.1 or 1.2, or with DTLS 1.0 or 1.2. It also applies to implementations of SSL 3.0 and TLS 1.0 that incorporate countermeasures to deal with previous padding oracle attacks. All TLS/DTLS ciphersuites that include CBC-mode encryption are potentially vulnerable. The paper indicates that with OpenSSL, a full plaintext recovery attack is possible, and with GnuTLS, a partial plaintext recovery is possible (recovering up to 4 bits of the last byte in any block of plaintext). To perform a successful attack, when TLS is used, a large number of TLS sessions are required (target plaintext must be sent repeatedly in the same position in the plaintext stream across the sessions). For DTLS, a successful attack can be carried out in a single session. The attacker must also be located close to the machine being attacked. Further details are noted in the paper. Current status of fixes in various implementations: * OpenSSL has a patch in development * NSS has a patch in development * GnuTLS is fixed in versions 2.12.23, 3.0.28, and 3.1.7 * PolarSSL is fixed in version 1.2.5 * BouncyCastle has a patch that will be included in the forthcoming 1.48 version External References: http://www.isg.rhul.ac.uk/tls/ http://www.isg.rhul.ac.uk/tls/TLStiming.pdf http://www.gnutls.org/security.html#GNUTLS-SA-2013-1 https://polarssl.org/tech-updates/releases/polarssl-1.2.5-released
GnuTLS fix: 2.12.x: https://gitorious.org/gnutls/gnutls/commit/458c67cf98740e7b12404f6c30e0d5317d56fd30 https://gitorious.org/gnutls/gnutls/commit/93b7fcfa3297a9123630704668b2946f602b910e 3.0.x: https://gitorious.org/gnutls/gnutls/commit/8dc2822966f64dd9cf7dde9c7aacd80d49d3ffe5 3.2.x / master: https://gitorious.org/gnutls/gnutls/commit/328ee22c1b3951e060c7124c7cb1cee592c59bc0
gnutls-2.12.23 gnutls-3.1.7 In tree, should contain this fix.
Pidgin, Empathy and Telepathy can't connect to Google Talk anymore after upgrading to gnutls-3.1.7, please see bug 455800 for details.
(In reply to comment #2) > gnutls-2.12.23 > gnutls-3.1.7 > > In tree, should contain this fix. Thanks, Alon. May we proceed to stabilize =net-libs/gnutls-2.12.23 ?
(In reply to comment #4) > (In reply to comment #2) > > gnutls-2.12.23 > > gnutls-3.1.7 > > > > In tree, should contain this fix. > > Thanks, Alon. May we proceed to stabilize =net-libs/gnutls-2.12.23 ? Seems so, no issues so far. FYI the gnutls-3.1.7 was broken, gnutls-3.1.8 was released. Thanks!
Arches, please test and mark stable: =net-libs/gnutls-2.12.23 Target KEYWORDS: "alpha amd64 arm hppa ia64 m68k ~mips ppc ppc64 s390 sh sparc x86 ~amd64-fbsd ~x86-fbsd ~x86-interix ~amd64-linux ~x86-linux ~ppc-macos ~x64-macos ~x86-macos ~sparc-solaris ~x86-solaris"
amd64 stable
x86 stable
Stable for HPPA.
ppc done
CVE-2013-1619 (http://nvd.nist.gov/nvd.cfm?cvename=CVE-2013-1619): The TLS implementation in GnuTLS before 2.12.23, 3.0.x before 3.0.28, and 3.1.x before 3.1.7 does not properly consider timing side-channel attacks on a noncompliant MAC check operation during the processing of malformed CBC padding, which allows remote attackers to conduct distinguishing attacks and plaintext-recovery attacks via statistical analysis of timing data for crafted packets, a related issue to CVE-2013-0169.
sh stable
arm stable
ppc64 stable
alpha stable
ia64 stable
sparc stable
s390 stable
GLSA request filed.
crypto done.
m68k -> ~ only, removing from CC. Maintainers unCC'd themselves, did the cleanup myself.
This issue was resolved and addressed in GLSA 201310-18 at http://security.gentoo.org/glsa/glsa-201310-18.xml by GLSA coordinator Sergey Popov (pinkbyte).
