From 0e4690165b4beb6777b747b0aeb1646a301f41d9 Mon Sep 17 00:00:00 2001
From: "Dr. Matthias St. Pierre" <Matthias.St.Pierre@ncp-e.com>
Date: Sun, 16 Oct 2016 00:53:33 +0200
Subject: [PATCH] Fix leak of secrecy in ecdh_compute_key()
A temporary buffer containing g^xy was not cleared in ecdh_compute_key()
before freeing it, so the shared secret was leaked in memory.
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
---
crypto/ecdh/ech_ossl.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/crypto/ecdh/ech_ossl.c b/crypto/ecdh/ech_ossl.c
index df115cc262..d3b05247fe 100644
--- a/crypto/ecdh/ech_ossl.c
+++ b/crypto/ecdh/ech_ossl.c
@@ -212,7 +212,9 @@ static int ecdh_compute_key(void *out, size_t outlen, const EC_POINT *pub_key,
BN_CTX_end(ctx);
if (ctx)
BN_CTX_free(ctx);
- if (buf)
+ if (buf) {
+ OPENSSL_cleanse(buf, buflen);
OPENSSL_free(buf);
+ }
return (ret);
}
--
2.25.1