libvirt: fix CVE-2025-13193scarthgap

A flaw was found in libvirt. External inactive snapshots for
shut-down VMs are incorrectly created as world-readable, making it
possible for unprivileged users to inspect the guest OS contents.
This results in an information disclosure vulnerability.

Reference:
https://nvd.nist.gov/vuln/detail/CVE-2025-13193

Upstream-patch:
https://gitlab.com/libvirt/libvirt/-/commit/a379327d8abcde8ac8d3e16fe5e4ba6f790d767a

Signed-off-by: Praveen Kumar <praveen.kumar@windriver.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>

2 files changed, 41 insertions, 0 deletions

diff --git a/recipes-extended/libvirt/libvirt/CVE-2025-13193.patch b/recipes-extended/libvirt/libvirt/CVE-2025-13193.patch
new file mode 100644
index 00000000..1ce5de38
--- /dev/null
+++ b/recipes-extended/libvirt/libvirt/CVE-2025-13193.patch
@@ -0,0 +1,40 @@
+From a379327d8abcde8ac8d3e16fe5e4ba6f790d767a Mon Sep 17 00:00:00 2001
+From: Peter Krempa <pkrempa@redhat.com>
+Date: Wed, 12 Nov 2025 17:52:05 +0100
+Subject: [PATCH] qemu: snapshot: Set umask for 'qemu-img' when creating
+ external inactive snapshots
+
+External inactive snapshots are created by invoking 'qemu-img' which
+creates the file. Currently qemu-img creates image with mode 644 based
+on default umask as libvirt doesn't set any.
+
+Having a world-readable image is obviously wrong so set the umask to
+077 to have the file readable only by the owner.
+
+Resolves: https://bugs.debian.org/1120119
+
+CVE: CVE-2025-13193
+
+Upstream-Status: Backport [https://gitlab.com/libvirt/libvirt/-/commit/a379327d8abcde8ac8d3e16fe5e4ba6f790d767a]
+
+Signed-off-by: Praveen Kumar <praveen.kumar@windriver.com>
+---
+ src/qemu/qemu_snapshot.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+diff --git a/src/qemu/qemu_snapshot.c b/src/qemu/qemu_snapshot.c
+index 73ff533..9819448 100644
+--- a/src/qemu/qemu_snapshot.c
++++ b/src/qemu/qemu_snapshot.c
+@@ -233,6 +233,9 @@ qemuSnapshotCreateQcow2Files(virQEMUDriver *driver,
+                                          NULL)))
+             return -1;
+
++        /* ensure that new files are only readable by the user */
++        virCommandSetUmask(cmd, 0077);
++
+         /* adds cmd line arg: backing_fmt=format,backing_file=/path/to/backing/file */
+         virBufferAsprintf(&buf, "backing_fmt=%s,backing_file=",
+                           virStorageFileFormatTypeToString(defdisk->src->format));
+--
+2.40.0
diff --git a/recipes-extended/libvirt/libvirt_10.0.0.bb b/recipes-extended/libvirt/libvirt_10.0.0.bb
index 22193ff3..c6e6069c 100644
--- a/recipes-extended/libvirt/libvirt_10.0.0.bb
+++ b/recipes-extended/libvirt/libvirt_10.0.0.bb
@@ -37,6 +37,7 @@ SRC_URI = "http://libvirt.org/sources/libvirt-${PV}.tar.xz;name=libvirt \
            file://CVE-2024-1441.patch \
            file://CVE-2024-2494.patch \
            file://CVE-2024-4418.patch \
+           file://CVE-2025-13193.patch \
           "
 
 SRC_URI[libvirt.sha256sum] = "8ba2e72ec8bdd2418554a1474c42c35704c30174b7611eaf9a16544b71bcf00a"