diff --git a/kdc/httpkadmind.c b/kdc/httpkadmind.c
index de3c7b38b..697ae189e 100644
--- a/kdc/httpkadmind.c
+++ b/kdc/httpkadmind.c
@@ -1740,15 +1740,22 @@ mac_csrf_token(kadmin_request_desc r, krb5_storage *sp)
             ret = krb5_enomem(r->context);
     /* HMAC the token body and the client principal name */
     if (ret == 0) {
-        HMAC_Init_ex(ctx, princ.key_data[i].key_data_contents[0], princ.key_data[i].key_data_length[0], EVP_sha256(), NULL);
-        HMAC_Update(ctx, data.data, data.length);
-        HMAC_Update(ctx, r->cname, strlen(r->cname));
-        HMAC_Final(ctx, mac, &maclen);
-        krb5_data_free(&data);
-        data.length = maclen;
-        data.data = mac;
-        if (krb5_storage_write(sp, mac, maclen) != maclen)
+        if (HMAC_Init_ex(ctx, princ.key_data[i].key_data_contents[0],
+                         princ.key_data[i].key_data_length[0], EVP_sha256(),
+                         NULL) == 0) {
+            HMAC_CTX_cleanup(ctx);
             ret = krb5_enomem(r->context);
+        } else {
+            HMAC_Update(ctx, data.data, data.length);
+            HMAC_Update(ctx, r->cname, strlen(r->cname));
+            HMAC_Final(ctx, mac, &maclen);
+            HMAC_CTX_cleanup(ctx);
+            krb5_data_free(&data);
+            data.length = maclen;
+            data.data = mac;
+            if (krb5_storage_write(sp, mac, maclen) != maclen)
+                ret = krb5_enomem(r->context);
+        }
     }
     krb5_free_principal(r->context, p);
     if (freeit)
diff --git a/kdc/kx509.c b/kdc/kx509.c
index 26edef19c..a5f960929 100644
--- a/kdc/kx509.c
+++ b/kdc/kx509.c
@@ -157,9 +157,11 @@ verify_req_hash(krb5_context context,
     }
 
     HMAC_CTX_init(&ctx);
-    HMAC_Init_ex(&ctx,
-                 key->keyvalue.data, key->keyvalue.length,
-                 EVP_sha1(), NULL);
+    if (HMAC_Init_ex(&ctx, key->keyvalue.data, key->keyvalue.length,
+                     EVP_sha1(), NULL) == 0) {
+        HMAC_CTX_cleanup(&ctx);
+        return krb5_enomem(context);
+    }
     if (sizeof(digest) != HMAC_size(&ctx))
         krb5_abortx(context, "runtime error, hmac buffer wrong size in kx509");
     HMAC_Update(&ctx, version_2_0, sizeof(version_2_0));
@@ -186,14 +188,17 @@ calculate_reply_hash(krb5_context context,
                      krb5_keyblock *key,
                      Kx509Response *rep)
 {
-    krb5_error_code ret;
+    krb5_error_code ret = 0;
     HMAC_CTX ctx;
 
     HMAC_CTX_init(&ctx);
 
-    HMAC_Init_ex(&ctx, key->keyvalue.data, key->keyvalue.length,
-                 EVP_sha1(), NULL);
-    ret = krb5_data_alloc(rep->hash, HMAC_size(&ctx));
+    if (HMAC_Init_ex(&ctx, key->keyvalue.data, key->keyvalue.length,
+                     EVP_sha1(), NULL) == 0)
+        ret = krb5_enomem(context);
+
+    if (ret == 0)
+        ret = krb5_data_alloc(rep->hash, HMAC_size(&ctx));
     if (ret) {
         HMAC_CTX_cleanup(&ctx);
         return krb5_enomem(context);
diff --git a/lib/gssapi/ntlm/crypto.c b/lib/gssapi/ntlm/crypto.c
index a8c670c50..efa71d911 100644
--- a/lib/gssapi/ntlm/crypto.c
+++ b/lib/gssapi/ntlm/crypto.c
@@ -194,7 +194,10 @@ v2_sign_message(gss_buffer_t in,
     HMAC_CTX c;
 
     HMAC_CTX_init(&c);
-    HMAC_Init_ex(&c, signkey, 16, EVP_md5(), NULL);
+    if (HMAC_Init_ex(&c, signkey, 16, EVP_md5(), NULL) == 0) {
+        HMAC_CTX_cleanup(&c);
+        return GSS_S_FAILURE;
+    }
 
     encode_le_uint32(seq, hmac);
     HMAC_Update(&c, hmac, 4);
diff --git a/lib/hcrypto/hmac.c b/lib/hcrypto/hmac.c
index c5265310f..6b387ae90 100644
--- a/lib/hcrypto/hmac.c
+++ b/lib/hcrypto/hmac.c
@@ -167,7 +167,10 @@ HMAC(const EVP_MD *md,
     HMAC_CTX ctx;
 
     HMAC_CTX_init(&ctx);
-    HMAC_Init_ex(&ctx, key, key_size, md, NULL);
+    if (HMAC_Init_ex(&ctx, key, key_size, md, NULL) == 0) {
+        HMAC_CTX_cleanup(&ctx);
+        return NULL;
+    }
     HMAC_Update(&ctx, data, data_size);
     HMAC_Final(&ctx, hash, hash_len);
     HMAC_CTX_cleanup(&ctx);
diff --git a/lib/hcrypto/test_hmac.c b/lib/hcrypto/test_hmac.c
index 063a461cc..36a5626a7 100644
--- a/lib/hcrypto/test_hmac.c
+++ b/lib/hcrypto/test_hmac.c
@@ -51,7 +51,11 @@ main(int argc, char **argv)
 	              "\x6f\xd1\x52\x4d\x54\x58\x73\x0f\xf3\x24";
 
     HMAC_CTX_init(&c);
-    HMAC_Init_ex(&c, hmackey, hmackey_size, EVP_sha1(), NULL);
+    if (HMAC_Init_ex(&c, hmackey, hmackey_size, EVP_sha1(), NULL) == 0) {
+        HMAC_CTX_cleanup(&c);
+        printf("out of memory\n");
+        return 1;
+    }
     HMAC_Update(&c, buf, sizeof(buf));
     HMAC_Final(&c, hmac, &hmaclen);
     HMAC_CTX_cleanup(&c);
diff --git a/lib/hcrypto/validate.c b/lib/hcrypto/validate.c
index 562e5aa4d..4b655f262 100644
--- a/lib/hcrypto/validate.c
+++ b/lib/hcrypto/validate.c
@@ -276,7 +276,8 @@ check_hmac(void)
 	              "\x6f\xd1\x52\x4d\x54\x58\x73\x0f\xf3\x24";
 
     HMAC_CTX_init(&c);
-    HMAC_Init_ex(&c, hmackey, hmackey_size, EVP_sha1(), NULL);
+    if (HMAC_Init_ex(&c, hmackey, hmackey_size, EVP_sha1(), NULL) == 0)
+        errx(1, "HMAC_Init_ex() out of memory");
     HMAC_Update(&c, buf, sizeof(buf));
     HMAC_Final(&c, hmac, &hmaclen);
     HMAC_CTX_cleanup(&c);
diff --git a/lib/kafs/rxkad_kdf.c b/lib/kafs/rxkad_kdf.c
index 174fa3a61..88f499db3 100644
--- a/lib/kafs/rxkad_kdf.c
+++ b/lib/kafs/rxkad_kdf.c
@@ -89,12 +89,16 @@ rxkad_derive_des_key(const void *in, size_t insize, char out[8])
     /* stop when 8 bit counter wraps to 0 */
     for (i = 1; i; i++) {
 	HMAC_CTX_init(&mctx);
-	HMAC_Init_ex(&mctx, in, insize, EVP_md5(), NULL);
+	if (HMAC_Init_ex(&mctx, in, insize, EVP_md5(), NULL) == 0) {
+            HMAC_CTX_cleanup(&mctx);
+            return ENOMEM;
+        }
 	HMAC_Update(&mctx, &i, 1);
 	HMAC_Update(&mctx, label, sizeof(label));   /* includes label and separator */
 	HMAC_Update(&mctx, Lbuf, 4);
 	mdsize = sizeof(tmp);
 	HMAC_Final(&mctx, tmp, &mdsize);
+        HMAC_CTX_cleanup(&mctx);
 	memcpy(ktmp, tmp, 8);
 	DES_set_odd_parity(&ktmp);
 	if (!DES_is_weak_key(&ktmp)) {
diff --git a/lib/krb5/crypto-evp.c b/lib/krb5/crypto-evp.c
index a16b83cb0..a03cdca2e 100644
--- a/lib/krb5/crypto-evp.c
+++ b/lib/krb5/crypto-evp.c
@@ -137,8 +137,11 @@ _krb5_evp_hmac_iov(krb5_context context,
     if (ctx == NULL)
         return krb5_enomem(context);
 
-    HMAC_Init_ex(ctx, key->key->keyvalue.data, key->key->keyvalue.length,
-                 md, engine);
+    if (HMAC_Init_ex(ctx, key->key->keyvalue.data, key->key->keyvalue.length,
+                     md, engine) == 0) {
+        HMAC_CTX_free(ctx);
+        return krb5_enomem(context);
+    }
 
     for (i = 0; i < niov; i++) {
         if (_krb5_crypto_iov_should_sign(&iov[i])) {
diff --git a/lib/krb5/kx509.c b/lib/krb5/kx509.c
index bd5991fcb..55cd0f345 100644
--- a/lib/krb5/kx509.c
+++ b/lib/krb5/kx509.c
@@ -848,21 +848,28 @@ mk_kx509_req(krb5_context context,
 
     /* Add the the key and HMAC to the message */
     HMAC_CTX_init(&ctx);
-    HMAC_Init_ex(&ctx, kx509_ctx->hmac_key->keyvalue.data,
-                 kx509_ctx->hmac_key->keyvalue.length, EVP_sha1(), NULL);
-    HMAC_Update(&ctx, version_2_0, sizeof(version_2_0));
-    if (private_key || kx509_ctx->given_csr.data) {
-        HMAC_Update(&ctx, kx509_req.pk_key.data, kx509_req.pk_key.length);
+    if (HMAC_Init_ex(&ctx, kx509_ctx->hmac_key->keyvalue.data,
+                     kx509_ctx->hmac_key->keyvalue.length,
+                     EVP_sha1(), NULL) == 0) {
+        HMAC_CTX_cleanup(&ctx);
+        ret = krb5_enomem(context);
     } else {
-        /* Probe */
-        HMAC_Update(&ctx, kx509_req.authenticator.data, kx509_req.authenticator.length);
+        HMAC_Update(&ctx, version_2_0, sizeof(version_2_0));
+        if (private_key || kx509_ctx->given_csr.data) {
+            HMAC_Update(&ctx, kx509_req.pk_key.data, kx509_req.pk_key.length);
+        } else {
+            /* Probe */
+            HMAC_Update(&ctx, kx509_req.authenticator.data, kx509_req.authenticator.length);
+        }
+        HMAC_Final(&ctx, kx509_req.pk_hash.data, 0);
+        HMAC_CTX_cleanup(&ctx);
     }
-    HMAC_Final(&ctx, kx509_req.pk_hash.data, 0);
-    HMAC_CTX_cleanup(&ctx);
 
     /* Encode the message, prefix `version_2_0', output the result */
-    ASN1_MALLOC_ENCODE(Kx509Request, pre_req.data, pre_req.length, &kx509_req, &len, ret);
-    ret = krb5_data_alloc(req, pre_req.length + sizeof(version_2_0));
+    if (ret == 0)
+        ASN1_MALLOC_ENCODE(Kx509Request, pre_req.data, pre_req.length, &kx509_req, &len, ret);
+    if (ret == 0)
+        ret = krb5_data_alloc(req, pre_req.length + sizeof(version_2_0));
     if (ret == 0) {
         memcpy(req->data, version_2_0, sizeof(version_2_0));
         memcpy(((unsigned char *)req->data) + sizeof(version_2_0),
@@ -984,8 +991,13 @@ rd_kx509_resp(krb5_context context,
     }
 
     HMAC_CTX_init(&ctx);
-    HMAC_Init_ex(&ctx, kx509_ctx->hmac_key->keyvalue.data,
-                 kx509_ctx->hmac_key->keyvalue.length, EVP_sha1(), NULL);
+    if (HMAC_Init_ex(&ctx, kx509_ctx->hmac_key->keyvalue.data,
+                     kx509_ctx->hmac_key->keyvalue.length, EVP_sha1(), NULL) == 0) {
+        free_Kx509Response(&r);
+        HMAC_CTX_cleanup(&ctx);
+        return krb5_enomem(context);
+    }
+
     HMAC_Update(&ctx, version_2_0, sizeof(version_2_0));
 
     {
diff --git a/lib/krb5/sp800-108-kdf.c b/lib/krb5/sp800-108-kdf.c
index 37e06dec3..4a12067c6 100755
--- a/lib/krb5/sp800-108-kdf.c
+++ b/lib/krb5/sp800-108-kdf.c
@@ -73,7 +73,10 @@ _krb5_SP800_108_HMAC_KDF(krb5_context context,
 	unsigned char tmp[4];
 	size_t len;
 
-	HMAC_Init_ex(&c, kdf_K1->data, kdf_K1->length, md, NULL);
+        if (HMAC_Init_ex(&c, kdf_K1->data, kdf_K1->length, md, NULL) == 0) {
+            HMAC_CTX_cleanup(&c);
+            return krb5_enomem(context);
+        }
 
 	_krb5_put_int(tmp, i + 1, 4);
 	HMAC_Update(&c, tmp, 4);
diff --git a/lib/ntlm/ntlm.c b/lib/ntlm/ntlm.c
index 9670a9718..622aa6c25 100644
--- a/lib/ntlm/ntlm.c
+++ b/lib/ntlm/ntlm.c
@@ -1324,7 +1324,10 @@ heim_ntlm_v2_base_session(void *key, size_t len,
 
     /* Note: key is the NTLMv2 key */
     HMAC_CTX_init(&c);
-    HMAC_Init_ex(&c, key, len, EVP_md5(), NULL);
+    if (HMAC_Init_ex(&c, key, len, EVP_md5(), NULL) == 0) {
+        HMAC_CTX_cleanup(&c);
+        return ENOMEM;
+    }
     HMAC_Update(&c, ntlmResponse->data, 16);
     HMAC_Final(&c, session->data, &hmaclen);
     HMAC_CTX_cleanup(&c);
@@ -1443,7 +1446,7 @@ heim_ntlm_build_ntlm2_master(void *key, size_t len,
 
     ret = heim_ntlm_v2_base_session(key, len, blob, &sess);
     if (ret)
-	return ret;
+        return ret;
 
     ret = heim_ntlm_keyex_wrap(&sess, session, master);
     heim_ntlm_free_buf(&sess);
@@ -1523,25 +1526,26 @@ heim_ntlm_ntlmv2_key(const void *key, size_t len,
 {
     int ret;
     unsigned int hmaclen;
+    struct ntlm_buf buf;
     HMAC_CTX c;
 
     HMAC_CTX_init(&c);
-    HMAC_Init_ex(&c, key, len, EVP_md5(), NULL);
-    {
-	struct ntlm_buf buf;
-	/* uppercase username and turn it into ucs2-le */
-	ret = ascii2ucs2le(username, 1, &buf);
-	if (ret)
-	    goto out;
-	HMAC_Update(&c, buf.data, buf.length);
-	free(buf.data);
-	/* turn target into ucs2-le */
-	ret = ascii2ucs2le(target, upper_case_target, &buf);
-	if (ret)
-	    goto out;
-	HMAC_Update(&c, buf.data, buf.length);
-	free(buf.data);
+    if (HMAC_Init_ex(&c, key, len, EVP_md5(), NULL) == 0) {
+        ret = ENOMEM;
+        goto out;
     }
+    /* uppercase username and turn it into ucs2-le */
+    ret = ascii2ucs2le(username, 1, &buf);
+    if (ret)
+        goto out;
+    HMAC_Update(&c, buf.data, buf.length);
+    free(buf.data);
+    /* turn target into ucs2-le */
+    ret = ascii2ucs2le(target, upper_case_target, &buf);
+    if (ret)
+        goto out;
+    HMAC_Update(&c, buf.data, buf.length);
+    free(buf.data);
     HMAC_Final(&c, ntlmv2, &hmaclen);
  out:
     HMAC_CTX_cleanup(&c);
@@ -1599,6 +1603,7 @@ heim_ntlm_calculate_lm2(const void *key, size_t len,
 			struct ntlm_buf *answer)
 {
     unsigned char clientchallenge[8];
+    krb5_error_code ret;
 
     if (RAND_bytes(clientchallenge, sizeof(clientchallenge)) != 1)
 	return HNTLM_ERR_RAND;
@@ -1612,12 +1617,12 @@ heim_ntlm_calculate_lm2(const void *key, size_t len,
         return ENOMEM;
     answer->length = 24;
 
-    heim_ntlm_derive_ntlm2_sess(ntlmv2, clientchallenge, 8,
-				serverchallenge, answer->data);
+    ret = heim_ntlm_derive_ntlm2_sess(ntlmv2, clientchallenge, 8,
+                                      serverchallenge, answer->data);
+    if (ret == 0)
+        memcpy(((unsigned char *)answer->data) + 16, clientchallenge, 8);
 
-    memcpy(((unsigned char *)answer->data) + 16, clientchallenge, 8);
-
-    return 0;
+    return ret;
 }
 
 
@@ -1695,7 +1700,10 @@ heim_ntlm_calculate_ntlm2(const void *key, size_t len,
     krb5_storage_free(sp);
     sp = NULL;
 
-    heim_ntlm_derive_ntlm2_sess(ntlmv2, data.data, data.length, serverchallenge, ntlmv2answer);
+    ret = heim_ntlm_derive_ntlm2_sess(ntlmv2, data.data, data.length,
+                                      serverchallenge, ntlmv2answer);
+    if (ret)
+        return ret;
 
     sp = krb5_storage_emem();
     if (sp == NULL) {
@@ -1809,10 +1817,13 @@ verify_ntlm2(const void *key, size_t len,
 	goto out;
     }
 
-    heim_ntlm_derive_ntlm2_sess(ntlmv2,
-				((unsigned char *)answer->data) + 16, answer->length - 16,
-				serverchallenge,
-				serveranswer);
+    ret = heim_ntlm_derive_ntlm2_sess(ntlmv2,
+                                      ((unsigned char *)answer->data) + 16,
+                                      answer->length - 16,
+                                      serverchallenge,
+                                      serveranswer);
+    if (ret)
+        goto out;
 
     if (memcmp(serveranswer, clientanswer, 16) != 0) {
 	heim_ntlm_free_buf(infotarget);
@@ -1995,7 +2006,7 @@ heim_ntlm_calculate_ntlm2_sess_hash(const unsigned char clnt_nonce[8],
  * @ingroup ntlm_core
  */
 
-void
+int
 heim_ntlm_derive_ntlm2_sess(const unsigned char sessionkey[16],
 			    const unsigned char *clnt_nonce, size_t clnt_nonce_length,
 			    const unsigned char svr_chal[8],
@@ -2006,10 +2017,14 @@ heim_ntlm_derive_ntlm2_sess(const unsigned char sessionkey[16],
 
     /* HMAC(Ksession, serverchallenge || clientchallenge) */
     HMAC_CTX_init(&c);
-    HMAC_Init_ex(&c, sessionkey, 16, EVP_md5(), NULL);
+    if (HMAC_Init_ex(&c, sessionkey, 16, EVP_md5(), NULL) == 0) {
+        HMAC_CTX_cleanup(&c);
+        return ENOMEM;
+    }
     HMAC_Update(&c, svr_chal, 8);
     HMAC_Update(&c, clnt_nonce, clnt_nonce_length);
     HMAC_Final(&c, derivedkey, &hmaclen);
     HMAC_CTX_cleanup(&c);
     memset(&c, 0, sizeof(c));
+    return 0;
 }