CVE-2025-37849: KVM: arm64: Tear down vGIC on failed vCPU creation
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Tear down vGIC on failed vCPU creation
If kvmarchvcpucreate() fails to share the vCPU page with the hypervisor, we propagate the error back to the ioctl but leave the vGIC vCPU data initialised. Note only does this leak the corresponding memory when the vCPU is destroyed but it can also lead to use-after-free if the redistributor device handling tries to walk into the vCPU.
Add the missing cleanup to kvmarchvcpucreate(), ensuring that the vGIC vCPU structures are destroyed on error.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.159-1Fixed in 6.1.170-3Fixed in 6.12.73-1Fixed in 6.12.86-1Fixed in 7.0.4-1 - Upgrade
Upgrade
debian/linux-6.1to a version that resolves this vulnerability.Fixed in 6.1.170-3~deb11u1 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.92.2-1
Event History
Frequently Asked Questions
What is the severity of CVE-2025-37849?
The severity of CVE-2025-37849 is rated as medium due to its impact on the virtual GIC in the Linux kernel.
How do I fix CVE-2025-37849?
To fix CVE-2025-37849, ensure that you apply the latest patches for the Linux kernel provided by your distribution.
What systems are affected by CVE-2025-37849?
CVE-2025-37849 affects various versions of the Linux kernel that utilize KVM on arm64 systems.
What is the impact of CVE-2025-37849?
The impact of CVE-2025-37849 can lead to unintended behavior during vCPU creation due to initialized vGIC data.
Is CVE-2025-37849 exploitable remotely?
CVE-2025-37849 is not directly exploitable remotely as it involves local interactions with the hypervisor.