From HEAD:

Fix flaw if 'Server Key exchange message' is omitted from a TLS
handshake which could lead to a cilent crash as found using the
Codenomicon TLS test suite (CVE-2008-1672)

Reviewed by: openssl-security@openssl.org

Obtained from: mark@awe.com

diff --git a/CHANGES b/CHANGES
index 5d6c7a8d0a529b83483110536346fc5c6a8cad65..f8b112ff1220ebb6e3b384cbd97517ff0a51304a 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -690,6 +690,11 @@
 
  Changes between 0.9.8g and 0.9.8h  [xx XXX xxxx]
 
+  *) Fix flaw if 'Server Key exchange message' is omitted from a TLS
+     handshake which could lead to a cilent crash as found using the
+     Codenomicon TLS test suite (CVE-2008-1672) 
+     [Steve Henson, Mark Cox]
+
   *) Fix double free in TLS server name extensions which could lead to
      a remote crash found by Codenomicon TLS test suite (CVE-2008-0891) 
      [Joe Orton]

diff --git a/ssl/s3_clnt.c b/ssl/s3_clnt.c
index 4ca47faf5117ff97553b3931e5aceb43acbe620b..23875f00e0e082b55548c03d151eba3e47ffb6f2 100644 (file)
--- a/ssl/s3_clnt.c
+++ b/ssl/s3_clnt.c
@@ -2143,6 +2143,13 @@ int ssl3_send_client_key_exchange(SSL *s)
                        {
                        DH *dh_srvr,*dh_clnt;
 
+                       if (s->session->sess_cert == NULL) 
+                               {
+                               ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_UNEXPECTED_MESSAGE);
+                               SSLerr(SSL_F_SSL3_SEND_CLIENT_KEY_EXCHANGE,SSL_R_UNEXPECTED_MESSAGE);
+                               goto err;
+                               }
+
                        if (s->session->sess_cert->peer_dh_tmp != NULL)
                                dh_srvr=s->session->sess_cert->peer_dh_tmp;
                        else