From db657a96ca37d87cceff14db66645ba17024803c Mon Sep 17 00:00:00 2001

From: Kamil Dudka <kdudka@redhat.com>

Date: Tue, 19 Mar 2019 13:16:53 +0100

Subject: [PATCH] Resolves: CVE-2019-3855 - fix integer overflow in transport read

... resulting in out of bounds write

Upstream-Patch: https://libssh2.org/1.8.0-CVE/CVE-2019-3855.patch

---

 src/transport.c | 6 +++++-

 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/transport.c b/src/transport.c

index 8725da0..5349284 100644

--- a/src/transport.c

+++ b/src/transport.c

@@ -434,8 +434,12 @@ int _libssh2_transport_read(LIBSSH2_SESSION * session)

              * and we can extract packet and padding length from it

              */

             p->packet_length = _libssh2_ntohu32(block);

-            if (p->packet_length < 1)

+            if(p->packet_length < 1) {

                 return LIBSSH2_ERROR_DECRYPT;

+            }

+            else if(p->packet_length > LIBSSH2_PACKET_MAXPAYLOAD) {

+                return LIBSSH2_ERROR_OUT_OF_BOUNDARY;

+            }

             p->padding_length = block[4];

-- 

2.17.2