- A use-after-free flaw was found in the way Openswan's pluto IKE daemon used cryptographic helpers. A remote, authenticated attacker could send a specially-crafted IKE packet that would crash the pluto daemon. This issue only affected SMP (symmetric multiprocessing) systems that have the cryptographic helpers enabled. The helpers are disabled by default on Red Hat Enterprise Linux 5, but enabled by default on Red Hat Enterprise Linux 6.
- When an NSS database is created with a password (either in FIPS or non-FIPS mode), access to a private key (associated with a certificate or a raw public key) requires authentication. At authentication time, openswan passes the database password to NSS. Previously, when this happened, openswan also logged the password to /var/log/secure. The password could also be seen by running "ipsec barf". With this update, openswan still passes the database password at authentication time but no longer logs it in any fashion.
- The pluto key management daemon terminated unexpectedly with a segmentation fault when removing a logical IP interface. With this update the code has been improved, pluto now withdraws a connection to a dead logical interface cleanly and no longer crashes in the scenario described.
- Due to an error in a buffer initialization, the following message may have been written to the /var/log/secure log file during the IKE negotiation: "size ([size]) differs from size specified in ISAKMP HDR ([size])". Consequently, the establishment of secure connections could be significantly delayed. This update applies an upstream patch that resolves this issue, and the establishment of IPsec connections is no longer delayed.
- With this update, the openswan packages now include support for message digest algorithm HMAC-SHA1-96 as per RFC 2404.
- RFC 5114, Additional Diffie-Hellman Groups for Use with IETF Standards, adds eight Diffie-Hellman groups (three prime modulus groups and five elliptic curve groups) to the extant 21 groups set out in previous RFCs (e.g. RFCs 2409, 3526 and 4492) for use with IKE, TLS, SSH and so on.This update implements groups 22, 23 and 24: a 1024-bit MODular exPonential (MODP) Group with 160-bit Prime Order Subgroup; a 2048-bit MODP Group with 224-bit Prime Order Subgroup; and a 2048-bit MODP Group with 256-bit Prime Order Subgroup respectively.
NoteImplementation of group 24 (a 2048-bit MODP Group with 256-bit Prime Order Subgroup) is required for US National Institute of Standards and Technology (NIST) IPv6 compliance and ongoing FIPS-140 certification.