diff --git a/crypto/asn1/a_type.c b/crypto/asn1/a_type.c
index 62bffde..75a17d5 100644
--- a/crypto/asn1/a_type.c
+++ b/crypto/asn1/a_type.c
@@ -111,7 +111,7 @@
 	}
 
 /* Returns 0 if they are equal, != 0 otherwise. */
-int ASN1_TYPE_cmp(ASN1_TYPE *a, ASN1_TYPE *b)
+int ASN1_TYPE_cmp(const ASN1_TYPE *a, const ASN1_TYPE *b)
 	{
 	int result = -1;
 
diff --git a/crypto/dsa/dsa.c b/crypto/dsa/dsa.c
index 25d15c0..47b902a 100644
--- a/crypto/dsa/dsa.c
+++ b/crypto/dsa/dsa.c
@@ -243,13 +243,21 @@
                const uint8_t *sig, size_t sig_len, const DSA *dsa) {
   DSA_SIG *s = NULL;
   int ret = -1, valid;
+  uint8_t *der = NULL;
 
   s = DSA_SIG_new();
   if (s == NULL) {
     goto err;
   }
 
-  if (d2i_DSA_SIG(&s, &sig, sig_len) == NULL) {
+  const uint8_t *sigp = sig;
+  if (d2i_DSA_SIG(&s, &sigp, sig_len) == NULL || sigp != sig + sig_len) {
+    goto err;
+  }
+
+  /* Ensure that the signature uses DER and doesn't have trailing garbage. */
+  int der_len = i2d_DSA_SIG(s, &der);
+  if (der_len < 0 || (size_t)der_len != sig_len || memcmp(sig, der, sig_len)) {
     goto err;
   }
 
@@ -260,6 +268,9 @@
   ret = valid;
 
 err:
+  if (der != NULL) {
+    OPENSSL_free(der);
+  }
   if (s) {
     DSA_SIG_free(s);
   }
diff --git a/crypto/ecdsa/ecdsa.c b/crypto/ecdsa/ecdsa.c
index ddc3e61..6442462 100644
--- a/crypto/ecdsa/ecdsa.c
+++ b/crypto/ecdsa/ecdsa.c
@@ -74,18 +74,31 @@
                  const uint8_t *sig, size_t sig_len, EC_KEY *eckey) {
   ECDSA_SIG *s;
   int ret = 0;
+  uint8_t *der = NULL;
 
   if (eckey->ecdsa_meth && eckey->ecdsa_meth->verify) {
     return eckey->ecdsa_meth->verify(digest, digest_len, sig, sig_len, eckey);
   }
 
   s = ECDSA_SIG_new();
-  if (s == NULL || d2i_ECDSA_SIG(&s, &sig, sig_len) == NULL) {
+  const uint8_t *sigp = sig;
+  if (s == NULL || d2i_ECDSA_SIG(&s, &sigp, sig_len) == NULL ||
+      sigp != sig + sig_len) {
     goto err;
   }
+
+  /* Ensure that the signature uses DER and doesn't have trailing garbage. */
+  const int der_len = i2d_ECDSA_SIG(s, &der);
+  if (der_len < 0 || (size_t) der_len != sig_len || memcmp(sig, der, sig_len)) {
+    goto err;
+  }
+
   ret = ECDSA_do_verify(digest, digest_len, s, eckey);
 
 err:
+  if (der != NULL) {
+    OPENSSL_free(der);
+  }
   if (s != NULL) {
     ECDSA_SIG_free(s);
   }
diff --git a/crypto/x509/a_verify.c b/crypto/x509/a_verify.c
index e728863..72e0a62 100644
--- a/crypto/x509/a_verify.c
+++ b/crypto/x509/a_verify.c
@@ -84,6 +84,12 @@
 		return 0;
 		}
 
+	if (signature->type == V_ASN1_BIT_STRING && signature->flags & 0x7)
+		{
+		OPENSSL_PUT_ERROR(X509, ASN1_item_verify, X509_R_INVALID_BIT_STRING_BITS_LEFT);
+		return 0;
+		}
+
 	EVP_MD_CTX_init(&ctx);
 
 	if (!EVP_DigestVerifyInitFromAlgorithm(&ctx, a, pkey))
diff --git a/crypto/x509/x509_error.c b/crypto/x509/x509_error.c
index d521281..222a40a 100644
--- a/crypto/x509/x509_error.c
+++ b/crypto/x509/x509_error.c
@@ -94,6 +94,7 @@
   {ERR_PACK(ERR_LIB_X509, 0, X509_R_CRL_VERIFY_FAILURE), "CRL_VERIFY_FAILURE"},
   {ERR_PACK(ERR_LIB_X509, 0, X509_R_ERR_ASN1_LIB), "ERR_ASN1_LIB"},
   {ERR_PACK(ERR_LIB_X509, 0, X509_R_IDP_MISMATCH), "IDP_MISMATCH"},
+  {ERR_PACK(ERR_LIB_X509, 0, X509_R_INVALID_BIT_STRING_BITS_LEFT), "INVALID_BIT_STRING_BITS_LEFT"},
   {ERR_PACK(ERR_LIB_X509, 0, X509_R_INVALID_DIRECTORY), "INVALID_DIRECTORY"},
   {ERR_PACK(ERR_LIB_X509, 0, X509_R_INVALID_FIELD_NAME), "INVALID_FIELD_NAME"},
   {ERR_PACK(ERR_LIB_X509, 0, X509_R_INVALID_TRUST), "INVALID_TRUST"},
diff --git a/crypto/x509/x_algor.c b/crypto/x509/x_algor.c
index 238b0f3..ae694e3 100644
--- a/crypto/x509/x_algor.c
+++ b/crypto/x509/x_algor.c
@@ -140,3 +140,15 @@
 	X509_ALGOR_set0(alg, OBJ_nid2obj(EVP_MD_type(md)), param_type, NULL);
 
 	}
+
+/* X509_ALGOR_cmp returns 0 if |a| and |b| are equal and non-zero otherwise. */
+int X509_ALGOR_cmp(const X509_ALGOR *a, const X509_ALGOR *b)
+	{
+	int rv;
+	rv = OBJ_cmp(a->algorithm, b->algorithm);
+	if (rv)
+		return rv;
+	if (!a->parameter && !b->parameter)
+		return 0;
+	return ASN1_TYPE_cmp(a->parameter, b->parameter);
+	}
diff --git a/crypto/x509/x_all.c b/crypto/x509/x_all.c
index cbc46e2..785fd1e 100644
--- a/crypto/x509/x_all.c
+++ b/crypto/x509/x_all.c
@@ -69,6 +69,8 @@
 
 int X509_verify(X509 *a, EVP_PKEY *r)
 	{
+	if (X509_ALGOR_cmp(a->sig_alg, a->cert_info->signature))
+		return 0;
 	return(ASN1_item_verify(ASN1_ITEM_rptr(X509_CINF),a->sig_alg,
 		a->signature,a->cert_info,r));
 	}
diff --git a/include/openssl/asn1.h b/include/openssl/asn1.h
index 9c606c0..fc12a75 100644
--- a/include/openssl/asn1.h
+++ b/include/openssl/asn1.h
@@ -739,7 +739,7 @@
 OPENSSL_EXPORT int ASN1_TYPE_get(ASN1_TYPE *a);
 OPENSSL_EXPORT void ASN1_TYPE_set(ASN1_TYPE *a, int type, void *value);
 OPENSSL_EXPORT int ASN1_TYPE_set1(ASN1_TYPE *a, int type, const void *value);
-OPENSSL_EXPORT int ASN1_TYPE_cmp(ASN1_TYPE *a, ASN1_TYPE *b);
+OPENSSL_EXPORT int ASN1_TYPE_cmp(const ASN1_TYPE *a, const ASN1_TYPE *b);
 
 OPENSSL_EXPORT ASN1_OBJECT *	ASN1_OBJECT_new(void );
 OPENSSL_EXPORT void		ASN1_OBJECT_free(ASN1_OBJECT *a);
diff --git a/include/openssl/x509.h b/include/openssl/x509.h
index d9c2ae1..475f747 100644
--- a/include/openssl/x509.h
+++ b/include/openssl/x509.h
@@ -720,6 +720,7 @@
 OPENSSL_EXPORT void X509_ALGOR_get0(ASN1_OBJECT **paobj, int *pptype, void **ppval,
 						X509_ALGOR *algor);
 OPENSSL_EXPORT void X509_ALGOR_set_md(X509_ALGOR *alg, const EVP_MD *md);
+OPENSSL_EXPORT int X509_ALGOR_cmp(const X509_ALGOR *a, const X509_ALGOR *b);
 
 OPENSSL_EXPORT X509_NAME *X509_NAME_dup(X509_NAME *xn);
 OPENSSL_EXPORT X509_NAME_ENTRY *X509_NAME_ENTRY_dup(X509_NAME_ENTRY *ne);
@@ -834,9 +835,6 @@
 OPENSSL_EXPORT void		X509_INFO_free(X509_INFO *a);
 OPENSSL_EXPORT char *		X509_NAME_oneline(X509_NAME *a,char *buf,int size);
 
-OPENSSL_EXPORT int ASN1_verify(i2d_of_void *i2d, X509_ALGOR *algor1,
-		ASN1_BIT_STRING *signature,char *data,EVP_PKEY *pkey);
-
 OPENSSL_EXPORT int ASN1_digest(i2d_of_void *i2d,const EVP_MD *type,char *data,
 		unsigned char *md,unsigned int *len);
 
@@ -1306,5 +1304,6 @@
 #define X509_R_CRL_ALREADY_DELTA 135
 #define X509_R_ERR_ASN1_LIB 136
 #define X509_R_AKID_MISMATCH 137
+#define X509_R_INVALID_BIT_STRING_BITS_LEFT 138
 
 #endif