libssh: Fix CVE-2026-3731

Pick commit according to [1]

[1] https://security-tracker.debian.org/tracker/CVE-2026-3731
[2] https://www.libssh.org/security/advisories/libssh-2026-sftp-extensions.txt

Skip the test file change as it's not available in libssh-0.8.9

Signed-off-by: Vijay Anusuri <vanusuri@mvista.com>
Signed-off-by: Gyorgy Sarvari <skandigraun@gmail.com>

meta-oe/recipes-support/libssh/libssh/CVE-2026-3731.patch

@@ -0,0 +1,44 @@
+From f80670a7aba86cbb442c9b115c9eaf4ca04601b8 Mon Sep 17 00:00:00 2001
+From: Jakub Jelen <jjelen@redhat.com>
+Date: Thu, 11 Dec 2025 13:22:44 +0100
+Subject: [PATCH] sftp: Fix out-of-bound read from sftp extensions
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Signed-off-by: Jakub Jelen <jjelen@redhat.com>
+Reviewed-by: Pavol Žá�ik <pzacik@redhat.com>
+(cherry picked from commit 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60)
+
+Upstream-Status: Backport [https://git.libssh.org/projects/libssh.git/commit/?id=f80670a7aba86cbb442c9b115c9eaf4ca04601b8]
+CVE: CVE-2026-3731
+Signed-off-by: Vijay Anusuri <vanusuri@mvista.com>
+---
+ src/sftp.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/src/sftp.c b/src/sftp.c
+index 43eb1ad6..be473793 100644
+--- a/src/sftp.c
++++ b/src/sftp.c
+@@ -686,7 +686,7 @@ const char *sftp_extensions_get_name(sftp_session sftp, unsigned int idx) {
+     return NULL;
+   }
+ 
+-  if (idx > sftp->ext->count) {
++  if (idx >= sftp->ext->count) {
+     ssh_set_error_invalid(sftp->session);
+     return NULL;
+   }
+@@ -702,7 +702,7 @@ const char *sftp_extensions_get_data(sftp_session sftp, unsigned int idx) {
+     return NULL;
+   }
+ 
+-  if (idx > sftp->ext->count) {
++  if (idx >= sftp->ext->count) {
+     ssh_set_error_invalid(sftp->session);
+     return NULL;
+   }
+-- 
+2.25.1
+

meta-oe/recipes-support/libssh/libssh_0.8.9.bb

@@ -28,6 +28,7 @@ SRC_URI = "git://git.libssh.org/projects/libssh.git;protocol=https;branch=stable
            file://CVE-2025-8277-2.patch \
            file://CVE-2025-8277-3.patch \
            file://CVE-2025-8114.patch \
+           file://CVE-2026-3731.patch \
           "
 SRCREV = "04685a74df9ce1db1bc116a83a0da78b4f4fa1f8"