Synopsis: Moderate: libreswan security and enhancement update
Advisory ID: SLSA-2015:1979-1
Issue Date: 2015-11-04
CVE Numbers: CVE-2015-3240
A flaw was discovered in the way Libreswan’s IKE daemon processed IKE KE
payloads. A remote attacker could send specially crafted IKE payload with
a KE payload of g^x=0 that, when processed, would lead to a denial of
service (daemon crash). (CVE-2015-3240)
Note: Please note that when upgrading from an earlier version of
Libreswan, the existing CA certificates in the /etc/ipsec.d/cacerts/
directory and the existing certificate revocation list (CRL) files from
the /etc/ipsec.d/crls/ directory are automatically imported into the NSS
database. Once completed, these directories are no longer used by
Libreswan. To install new CA certificates or new CRLS, the certutil and
crlutil commands must be used to import these directly into the Network
Security Services (NSS) database.
This update also adds the following enhancements:
* This update adds support for RFC 7383 IKEv2 Fragmentation, RFC 7619 Auth
Null and ID Null, INVALID_KE renegotiation, CRL and OCSP support via NSS,
AES_CTR and AES_GCM support for IKEv2, CAVS testing for FIPS compliance.
In addition, this update enforces FIPS algorithms restrictions in FIPS
mode, and runs Composite Application Validation System (CAVS) testing for
FIPS compliance during package build. A new Cryptographic Algorithm
Validation Program (CAVP) binary can be used to re-run the CAVS tests at
any time. Regardless of FIPS mode, the pluto daemon runs RFC test vectors
for various algorithms.
Furthermore, compiling on all architectures now enables the “-Werror” GCC
option, which enhances the security by making all warnings into errors.
* This update also fixes several memory leaks and introduces a sub-second
packet retransmit option.
* This update improves migration support from Openswan to Libreswan.
Specifically, all Openswan options that can take a time value without a
suffix are now supported, and several new keywords for use in the
/etc/ipsec.conf file have been introduced. See the relevant man pages for
* With this update, loopback support via the “loopback=” option has been
– Scientific Linux Development Team