commit 208d54db20d58c9a5e45e856a0650caadd7d9612
Author: Dr. Stephen Henson <steve@openssl.org>
Date: Tue May 13 18:48:31 2014 +0100
Fix for CVE-2014-0195
A buffer overrun attack can be triggered by sending invalid DTLS fragments
to an OpenSSL DTLS client or server. This is potentially exploitable to
run arbitrary code on a vulnerable client or server.
Fixed by adding consistency check for DTLS fragments.
Thanks to Jüri Aedla for reporting this issue.
diff --git a/ssl/d1_both.c b/ssl/d1_both.c
index 2e8cf68..07f67f8 100644
--- a/ssl/d1_both.c
+++ b/ssl/d1_both.c
@@ -627,7 +627,16 @@ dtls1_reassemble_fragment(SSL *s, struct hm_header_st* msg_hdr, int *ok)
frag->msg_header.frag_off = 0;
}
else
+ {
frag = (hm_fragment*) item->data;
+ if (frag->msg_header.msg_len != msg_hdr->msg_len)
+ {
+ item = NULL;
+ frag = NULL;
+ goto err;
+ }
+ }
+
/* If message is already reassembled, this must be a
* retransmit and can be dropped.