CVE-2020-25604 Race condition in n/a

What is CVE-2020-25604?

CVE-2020-25604 is a medium-severity vulnerability in Debian Debian Linux, published on 23 Sep 2020. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

An issue was discovered in Xen through 4.14.x. There is a race condition when migrating timers between x86 HVM vCPUs. When migrating timers of x86 HVM guests between its vCPUs, the locking model used allows for a second vCPU of the same guest (also operating on the timers) to release a lock that it didn't acquire. The most likely effect of the issue is a hang or crash of the hypervisor, i.e., a Denial of Service (DoS). All versions of Xen are affected. Only x86 systems are vulnerable. Arm systems are not vulnerable. Only x86 HVM guests can leverage the vulnerability. x86 PV and PVH cannot leverage the vulnerability. Only guests with more than one vCPU can exploit the vulnerability.

Weakness: CWE-362

Which versions are affected by CVE-2020-25604?

It affects 4 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Opensuse Leap, Xen Xen.

How do I fix CVE-2020-25604?

Apply the vendor's patch.

Is CVE-2020-25604 being exploited?

There is no known exploitation of CVE-2020-25604 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2020-25604, DEBIAN-CVE-2020-25604, GHSA-77g8-pq4g-f4jv, UBUNTU-CVE-2020-25604.