diff --git a/.gitignore b/.gitignore
index 3391da3..1fac0c2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -18,3 +18,4 @@ libguestfs-1.5.3.tar.gz
 /libguestfs-1.5.20.tar.gz
 /libguestfs-1.5.21.tar.gz
 /libguestfs-1.5.22.tar.gz
+/libguestfs-1.5.23.tar.gz
diff --git a/libguestfs.spec b/libguestfs.spec
index d5493b2..0e455a8 100644
--- a/libguestfs.spec
+++ b/libguestfs.spec
@@ -41,7 +41,7 @@
 Summary:       Access and modify virtual machine disk images
 Name:          libguestfs
 Epoch:         1
-Version:       1.5.22
+Version:       1.5.23
 Release:       1%{?dist}
 License:       LGPLv2+
 Group:         Development/Libraries
@@ -739,6 +739,10 @@ rm -rf $RPM_BUILD_ROOT
 
 
 %changelog
+* Sat Oct 23 2010 Richard Jones <rjones@redhat.com> - 1:1.5.23-1
+- Fix for libguestfs: missing disk format specifier when adding a disk
+  (RHBZ#642934, CVE-2010-3851).
+
 * Tue Oct 19 2010 Richard Jones <rjones@redhat.com> - 1:1.5.22-1
 - New upstream development version 1.5.22.
 
diff --git a/sources b/sources
index 2818559..5c91a63 100644
--- a/sources
+++ b/sources
@@ -1 +1 @@
-3fd8b770458a1e000689202a963e8b8c  libguestfs-1.5.22.tar.gz
+cfa4485737583cbf7991840d2441b0d6  libguestfs-1.5.23.tar.gz