Description
The qemuAgentCommand function in libvirt before 1.1.1, when a guest agent is not configured, allows remote attackers to cause a denial of service (NULL pointer dereference and crash) via vectors related to "agent based cpu (un)plug," as demonstrated by the "virsh vcpucount foobar --guest" command.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libvirt | 1.1.0-4 | — |
| Debian 13 | libvirt | 1.1.0-4 | — |
| Debian 12 | libvirt | 1.1.0-4 | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libvirt | 2.5.0-1.1 | openSUSE-SU-2024:10209-1 |
Advisories 1
- openSUSE-SU-2024:10209-1 libvirt-2.5.0-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
References
- http://libvirt.org/git/?p=libvirt.git%3Ba=commitdiff%3Bh=96518d4316b711c72205117f8d5c967d5127bbb6
- http://libvirt.org/news.html
- https://bugzilla.redhat.com/show_bug.cgi?id=984821
- https://bugzilla.redhat.com/show_bug.cgi?id=986386
- [oss-security] 20130719 Re: CVE request -- libvirt: crash of libvirtd without guest agent configuration mailing-list