Add NULL checks where ContentInfo data can be NULL

PKCS12 structures contain PKCS7 ContentInfo fields. These fields are optional and can be NULL even if the "type" is a valid value. OpenSSL was not properly accounting for this and a NULL dereference can occur causing a crash. CVE-2024-0727
Tongsuo-Project · Apr 15, 2024 · fc6bbe4 · fc6bbe4
1 parent c240731
commit fc6bbe4
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Showing 7 changed files with 38 additions and 6 deletions.
diff --git a/crypto/err/openssl.txt b/crypto/err/openssl.txt
@@ -1011,6 +1011,7 @@ PKCS12_F_PKCS12_SETUP_MAC:122:PKCS12_setup_mac
 PKCS12_F_PKCS12_SET_MAC:123:PKCS12_set_mac
 PKCS12_F_PKCS12_UNPACK_AUTHSAFES:130:PKCS12_unpack_authsafes
 PKCS12_F_PKCS12_UNPACK_P7DATA:131:PKCS12_unpack_p7data
+PKCS12_F_PKCS12_UNPACK_P7ENCDATA:134:PKCS12_unpack_p7encdata
 PKCS12_F_PKCS12_VERIFY_MAC:126:PKCS12_verify_mac
 PKCS12_F_PKCS8_ENCRYPT:125:PKCS8_encrypt
 PKCS12_F_PKCS8_SET0_PBE:132:PKCS8_set0_pbe

diff --git a/crypto/pkcs12/p12_add.c b/crypto/pkcs12/p12_add.c
@@ -76,6 +76,12 @@ STACK_OF(PKCS12_SAFEBAG) *PKCS12_unpack_p7data(PKCS7 *p7)
                   PKCS12_R_CONTENT_TYPE_NOT_DATA);
         return NULL;
     }
+
+    if (p7->d.data == NULL) {
+        PKCS12err(PKCS12_F_PKCS12_UNPACK_P7DATA, PKCS12_R_DECODE_ERROR);
+        return NULL;
+    }
+
     return ASN1_item_unpack(p7->d.data, ASN1_ITEM_rptr(PKCS12_SAFEBAGS));
 }
 
@@ -132,6 +138,12 @@ STACK_OF(PKCS12_SAFEBAG) *PKCS12_unpack_p7encdata(PKCS7 *p7, const char *pass,
 {
     if (!PKCS7_type_is_encrypted(p7))
         return NULL;
+
+    if (p7->d.encrypted == NULL) {
+        PKCS12err(PKCS12_F_PKCS12_UNPACK_P7ENCDATA, PKCS12_R_DECODE_ERROR);
+        return NULL;
+    }
+
     return PKCS12_item_decrypt_d2i(p7->d.encrypted->enc_data->algorithm,
                                    ASN1_ITEM_rptr(PKCS12_SAFEBAGS),
                                    pass, passlen,
@@ -159,6 +171,12 @@ STACK_OF(PKCS7) *PKCS12_unpack_authsafes(const PKCS12 *p12)
                   PKCS12_R_CONTENT_TYPE_NOT_DATA);
         return NULL;
     }
+
+    if (p12->authsafes->d.data == NULL) {
+        PKCS12err(PKCS12_F_PKCS12_UNPACK_AUTHSAFES, PKCS12_R_DECODE_ERROR);
+        return NULL;
+    }
+
     return ASN1_item_unpack(p12->authsafes->d.data,
                             ASN1_ITEM_rptr(PKCS12_AUTHSAFES));
 }
diff --git a/crypto/pkcs12/p12_mutl.c b/crypto/pkcs12/p12_mutl.c
@@ -93,6 +93,11 @@ static int pkcs12_gen_mac(PKCS12 *p12, const char *pass, int passlen,
         return 0;
     }
 
+    if (p12->authsafes->d.data == NULL) {
+        PKCS12err(PKCS12_F_PKCS12_GEN_MAC, PKCS12_R_DECODE_ERROR);
+        return 0;
+    }
+
     salt = p12->mac->salt->data;
     saltlen = p12->mac->salt->length;
     if (!p12->mac->iter)

diff --git a/crypto/pkcs12/p12_npas.c b/crypto/pkcs12/p12_npas.c
@@ -78,8 +78,9 @@ static int newpass_p12(PKCS12 *p12, const char *oldpass, const char *newpass)
             bags = PKCS12_unpack_p7data(p7);
         } else if (bagnid == NID_pkcs7_encrypted) {
             bags = PKCS12_unpack_p7encdata(p7, oldpass, -1);
-            if (!alg_get(p7->d.encrypted->enc_data->algorithm,
-                         &pbe_nid, &pbe_iter, &pbe_saltlen))
+            if (p7->d.encrypted == NULL
+                    || !alg_get(p7->d.encrypted->enc_data->algorithm,
+                                &pbe_nid, &pbe_iter, &pbe_saltlen))
                 goto err;
         } else {
             continue;

diff --git a/crypto/pkcs12/pk12err.c b/crypto/pkcs12/pk12err.c
@@ -1,6 +1,6 @@
 /*
  * Generated by util/mkerr.pl DO NOT EDIT
- * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2024 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -58,6 +58,8 @@ static const ERR_STRING_DATA PKCS12_str_functs[] = {
      "PKCS12_unpack_authsafes"},
     {ERR_PACK(ERR_LIB_PKCS12, PKCS12_F_PKCS12_UNPACK_P7DATA, 0),
      "PKCS12_unpack_p7data"},
+    {ERR_PACK(ERR_LIB_PKCS12, PKCS12_F_PKCS12_UNPACK_P7ENCDATA, 0),
+     "PKCS12_unpack_p7encdata"},
     {ERR_PACK(ERR_LIB_PKCS12, PKCS12_F_PKCS12_VERIFY_MAC, 0),
      "PKCS12_verify_mac"},
     {ERR_PACK(ERR_LIB_PKCS12, PKCS12_F_PKCS8_ENCRYPT, 0), "PKCS8_encrypt"},

diff --git a/crypto/pkcs7/pk7_mime.c b/crypto/pkcs7/pk7_mime.c
@@ -30,10 +30,14 @@ int SMIME_write_PKCS7(BIO *bio, PKCS7 *p7, BIO *data, int flags)
 {
     STACK_OF(X509_ALGOR) *mdalgs;
     int ctype_nid = OBJ_obj2nid(p7->type);
-    if (ctype_nid == NID_pkcs7_signed)
+
+    if (ctype_nid == NID_pkcs7_signed) {
+        if (p7->d.sign == NULL)
+            return 0;
         mdalgs = p7->d.sign->md_algs;
-    else
+    } else {
         mdalgs = NULL;
+    }
 
     flags ^= SMIME_OLDMIME;
 

diff --git a/include/openssl/pkcs12err.h b/include/openssl/pkcs12err.h
@@ -1,6 +1,6 @@
 /*
  * Generated by util/mkerr.pl DO NOT EDIT
- * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2024 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -47,6 +47,7 @@ int ERR_load_PKCS12_strings(void);
 # define PKCS12_F_PKCS12_SET_MAC                          123
 # define PKCS12_F_PKCS12_UNPACK_AUTHSAFES                 130
 # define PKCS12_F_PKCS12_UNPACK_P7DATA                    131
+# define PKCS12_F_PKCS12_UNPACK_P7ENCDATA                 134
 # define PKCS12_F_PKCS12_VERIFY_MAC                       126
 # define PKCS12_F_PKCS8_ENCRYPT                           125
 # define PKCS12_F_PKCS8_SET0_PBE                          132