CVE: CVE-2017-9526 Upstream-Status: Backport Signed-off-by: Ross Burton From b3cab278eb9c2ceda79f980bc26460d97f260041 Mon Sep 17 00:00:00 2001 From: Jo Van Bulck Date: Thu, 19 Jan 2017 17:00:15 +0100 Subject: [PATCH] ecc: Store EdDSA session key in secure memory. * cipher/ecc-eddsa.c (_gcry_ecc_eddsa_sign): use mpi_snew to allocate session key. -- An attacker who learns the EdDSA session key from side-channel observation during the signing process, can easily revover the long- term secret key. Storing the session key in secure memory ensures that constant time point operations are used in the MPI library. Signed-off-by: Jo Van Bulck --- cipher/ecc-eddsa.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/cipher/ecc-eddsa.c b/cipher/ecc-eddsa.c index f91f8489..813e030d 100644 --- a/cipher/ecc-eddsa.c +++ b/cipher/ecc-eddsa.c @@ -603,7 +603,7 @@ _gcry_ecc_eddsa_sign (gcry_mpi_t input, ECC_secret_key *skey, a = mpi_snew (0); x = mpi_new (0); y = mpi_new (0); - r = mpi_new (0); + r = mpi_snew (0); ctx = _gcry_mpi_ec_p_internal_new (skey->E.model, skey->E.dialect, 0, skey->E.p, skey->E.a, skey->E.b); b = (ctx->nbits+7)/8; -- 2.11.0