diff --git a/src/wp_ecdsa_sig.c b/src/wp_ecdsa_sig.c
index 75752524..af56de4a 100644
--- a/src/wp_ecdsa_sig.c
+++ b/src/wp_ecdsa_sig.c
@@ -185,14 +185,20 @@ static int wp_ecdsa_signverify_init(wp_EcdsaSigCtx *ctx, wp_Ecc* ecc,
 {
     int ok = 1;
 
-    if (ctx->ecc != ecc) {
-        wp_ecc_free(ctx->ecc);
+    if (ctx == NULL || (ecc == NULL && ctx->ecc == NULL)) {
+        ok = 0;
+    }
+    else if (ecc != NULL) {
         if (!wp_ecc_up_ref(ecc)) {
             ok = 0;
         }
+        if (ok) {
+            wp_ecc_free(ctx->ecc);
+            ctx->ecc = ecc;
+        }
     }
+
     if (ok) {
-        ctx->ecc = ecc;
         ctx->op = op;
 
         if (!wp_ecdsa_set_ctx_params(ctx, params)) {
diff --git a/src/wp_ecx_sig.c b/src/wp_ecx_sig.c
index 76ddc0c9..15119532 100644
--- a/src/wp_ecx_sig.c
+++ b/src/wp_ecx_sig.c
@@ -188,14 +188,19 @@ static int wp_ecx_digest_signverify_init(wp_EcxSigCtx *ctx,
         ok = 0;
     }
 
-    if (ok && (ctx->ecx != ecx)) {
-        wp_ecx_free(ctx->ecx);
+    if (ok && (ctx == NULL || (ctx->ecx == NULL && ecx == NULL))) {
+        ok = 0;
+    }
+    else if (ok && ecx != NULL) {
         if (!wp_ecx_up_ref(ecx)) {
             ok = 0;
         }
+        if (ok) {
+            wp_ecx_free(ctx->ecx);
+            ctx->ecx = ecx;
+        }
     }
     if (ok) {
-        ctx->ecx = ecx;
         ctx->op = op;
     }
 
diff --git a/src/wp_rsa_sig.c b/src/wp_rsa_sig.c
index 23dd96b7..55d33ec0 100644
--- a/src/wp_rsa_sig.c
+++ b/src/wp_rsa_sig.c
@@ -455,16 +455,15 @@ static int wp_rsa_signverify_init(wp_RsaSigCtx* ctx, wp_Rsa* rsa,
 {
     int ok = 1;
 
-    if ((ctx == NULL) || (rsa == NULL)) {
+    if ((ctx == NULL) || (ctx->rsa == NULL && rsa == NULL)) {
         ok = 0;
     }
-    if (ok && (ctx->rsa != rsa)) {
-        wp_rsa_free(ctx->rsa);
-        ctx->rsa = NULL;
+    else if (rsa != NULL) {
         if (!wp_rsa_up_ref(rsa)) {
             ok = 0;
         }
-        else {
+        if (ok) {
+            wp_rsa_free(ctx->rsa);
             ctx->rsa = rsa;
         }
     }
diff --git a/test/test_ecc.c b/test/test_ecc.c
index e38e5b5d..ab67ec9a 100644
--- a/test/test_ecc.c
+++ b/test/test_ecc.c
@@ -2005,5 +2005,54 @@ int test_ec_import(void* data)
     return err;
 }
 
+static int test_ec_null_sign_init_ex(OSSL_LIB_CTX *libCtx)
+{
+#ifndef WP_HAVE_EC_P256
+    (void)libCtx;
+    PRINT_MSG("Skipping test - WP_HAVE_EC_P256 not defined");
+    return 0;
+#else
+    int err = 0;
+    EVP_MD_CTX *ctx = NULL;
+    EVP_MD *md = NULL;
+    EVP_PKEY *pkey = NULL;
+    const unsigned char *p = ecc_key_der_256;
+
+    err = (ctx = EVP_MD_CTX_new()) == NULL;
+    if (err == 0) {
+        md = EVP_MD_fetch(libCtx, "SHA256", NULL);
+        err = md == NULL;
+    }
+    if (err == 0) {
+        pkey = d2i_PrivateKey(EVP_PKEY_EC, NULL, &p, sizeof(ecc_key_der_256));
+        err = pkey == NULL;
+    }
+    if (err == 0) {
+        err = EVP_DigestSignInit_ex(ctx, NULL, "SHA256", libCtx, NULL, pkey, NULL) != 1;
+    }
+    if (err == 0) {
+        err = EVP_DigestSignInit_ex(ctx, NULL, "SHA256", libCtx, NULL, NULL, NULL) != 1;
+    }
+
+    EVP_PKEY_free(pkey);
+    EVP_MD_free(md);
+    EVP_MD_CTX_free(ctx);
+
+    return err;
+#endif
+}
+
+int test_ec_null_init(void* data)
+{
+    int err = 0;
+    (void)data;
+
+    err = test_ec_null_sign_init_ex(osslLibCtx);
+    if (err == 0) {
+        err = test_ec_null_sign_init_ex(wpLibCtx);
+    }
+
+    return err;
+}
 
 #endif /* WP_HAVE_ECC */
diff --git a/test/test_ecx.c b/test/test_ecx.c
index dd70b222..31773652 100644
--- a/test/test_ecx.c
+++ b/test/test_ecx.c
@@ -626,4 +626,53 @@ int test_ecx_misc(void *data)
     return err;
 }
 
+static int test_ecx_null_sign_init_ex(OSSL_LIB_CTX *libCtx)
+{
+    int err = 0;
+    EVP_MD_CTX *ctx = NULL;
+    EVP_MD *md = NULL;
+    EVP_PKEY *pkey = NULL;
+#ifdef WP_HAVE_ED25519
+    const unsigned char *p = ed25519_key_der;
+#endif
+
+#ifndef WP_HAVE_ED25519
+    (void)libCtx;
+    (void)provider_name;
+    PRINT_MSG("Skipping test - WP_HAVE_ED25519 not defined");
+    return 0;
+#endif
+
+    err = (ctx = EVP_MD_CTX_new()) == NULL;
+    if (err == 0) {
+        pkey = d2i_PrivateKey(EVP_PKEY_ED25519, NULL, &p, sizeof(ed25519_key_der));
+        err = pkey == NULL;
+    }
+    if (err == 0) {
+        err = EVP_DigestSignInit_ex(ctx, NULL, NULL, libCtx, NULL, pkey, NULL) != 1;
+    }
+    if (err == 0) {
+        err = EVP_DigestSignInit_ex(ctx, NULL, NULL, libCtx, NULL, NULL, NULL) != 1;
+    }
+
+    EVP_PKEY_free(pkey);
+    EVP_MD_free(md);
+    EVP_MD_CTX_free(ctx);
+
+    return err;
+}
+
+int test_ecx_null_init(void* data)
+{
+    int err = 0;
+    (void)data;
+
+    err = test_ecx_null_sign_init_ex(osslLibCtx);
+    if (err == 0) {
+        err = test_ecx_null_sign_init_ex(wpLibCtx);
+    }
+
+    return err;
+}
+
 #endif /* defined(WP_HAVE_ED25519) || defined(WP_HAVE_ECD444) */
diff --git a/test/test_rsa.c b/test/test_rsa.c
index 9c511976..79164d72 100644
--- a/test/test_rsa.c
+++ b/test/test_rsa.c
@@ -1615,4 +1615,48 @@ int test_rsa_decode(void* data)
     return err;
 }
 
+static int test_rsa_null_sign_init_ex(OSSL_LIB_CTX *libCtx)
+{
+    int err = 0;
+    EVP_MD_CTX *ctx = NULL;
+    EVP_MD *md = NULL;
+    EVP_PKEY *pkey = NULL;
+    const unsigned char *p = rsa_key_der_2048;
+
+    err = (ctx = EVP_MD_CTX_new()) == NULL;
+    if (err == 0) {
+        md = EVP_MD_fetch(libCtx, "SHA256", NULL);
+        err = md == NULL;
+    }
+    if (err == 0) {
+        pkey = d2i_PrivateKey(EVP_PKEY_RSA, NULL, &p, sizeof(rsa_key_der_2048));
+        err = pkey == NULL;
+    }
+    if (err == 0) {
+        err = EVP_DigestSignInit_ex(ctx, NULL, "SHA256", libCtx, NULL, pkey, NULL) != 1;
+    }
+    if (err == 0) {
+        err = EVP_DigestSignInit_ex(ctx, NULL, "SHA256", libCtx, NULL, NULL, NULL) != 1;
+    }
+
+    EVP_PKEY_free(pkey);
+    EVP_MD_free(md);
+    EVP_MD_CTX_free(ctx);
+
+    return err;
+}
+
+int test_rsa_null_init(void* data)
+{
+    int err = 0;
+    (void)data;
+
+    err = test_rsa_null_sign_init_ex(osslLibCtx);
+    if (err == 0) {
+        err = test_rsa_null_sign_init_ex(wpLibCtx);
+    }
+
+    return err;
+}
+
 #endif /* WP_HAVE_RSA */
diff --git a/test/unit.c b/test/unit.c
index fbd3bee2..bb64fafe 100644
--- a/test/unit.c
+++ b/test/unit.c
@@ -170,6 +170,7 @@ TEST_CASE test_case[] = {
     TEST_DECL(test_rsa_load_cert, NULL),
     TEST_DECL(test_rsa_fromdata, NULL),
     TEST_DECL(test_rsa_decode, NULL),
+    TEST_DECL(test_rsa_null_init, NULL),
 #endif /* WP_HAVE_RSA */
 #ifdef WP_HAVE_EC_P192
     #ifdef WP_HAVE_ECKEYGEN
@@ -217,6 +218,7 @@ TEST_CASE test_case[] = {
     #endif
     TEST_DECL(test_ec_decode, NULL),
     TEST_DECL(test_ec_import, NULL),
+    TEST_DECL(test_ec_null_init, NULL),
 #endif
 #ifdef WP_HAVE_EC_P384
     #ifdef WP_HAVE_ECKEYGEN
@@ -286,6 +288,7 @@ TEST_CASE test_case[] = {
     TEST_DECL(test_ecx_sign_verify_raw_priv, NULL),
     TEST_DECL(test_ecx_sign_verify_raw_pub, NULL),
     TEST_DECL(test_ecx_misc, NULL),
+    TEST_DECL(test_ecx_null_init, NULL),
 #endif
 };
 #define TEST_CASE_CNT   (int)(sizeof(test_case) / sizeof(*test_case))
diff --git a/test/unit.h b/test/unit.h
index 1e1aad39..c836ed46 100644
--- a/test/unit.h
+++ b/test/unit.h
@@ -248,6 +248,7 @@ int test_rsa_load_key(void* data);
 int test_rsa_load_cert(void* data);
 int test_rsa_fromdata(void* data);
 int test_rsa_decode(void* data);
+int test_rsa_null_init(void* data);
 #endif /* WP_HAVE_RSA */
 
 #ifdef WP_HAVE_DH
@@ -375,6 +376,7 @@ int test_ec_load_cert(void* data);
 
 int test_ec_decode(void* data);
 int test_ec_import(void* data);
+int test_ec_null_init(void* data);
 
 #endif /* WP_HAVE_ECC */
 
@@ -387,6 +389,7 @@ int test_ecx_sign_verify(void *data);
 int test_ecx_sign_verify_raw_priv(void *data);
 int test_ecx_sign_verify_raw_pub(void *data);
 int test_ecx_misc(void *data);
+int test_ecx_null_init(void *data);
 #endif
 
 #endif /* UNIT_H */