CVE-2020-25601

Name
CVE-2020-25601
Description
An issue was discovered in Xen through 4.14.x. There is a lack of preemption in evtchn_reset() / evtchn_destroy(). In particular, the FIFO event channel model allows guests to have a large number of event channels active at a time. Closing all of these (when resetting all event channels or when cleaning up after the guest) may take extended periods of time. So far, there was no arrangement for preemption at suitable intervals, allowing a CPU to spend an almost unbounded amount of time in the processing of these operations. Malicious or buggy guest kernels can mount a Denial of Service (DoS) attack affecting the entire system. All Xen versions are vulnerable in principle. Whether versions 4.3 and older are vulnerable depends on underlying hardware characteristics.
NVD Severity
medium
Other trackers
Mailing lists
Exploits
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
Vendor Advisory https://xenbits.xen.org/xsa/advisory-344.html
Third Party Advisory https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4JRXMKEMQRQYWYEPHVBIWUEAVQ3LU4FN/
Third Party Advisory https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DA633Y3G5KX7MKRN4PFEGM3IVTJMBEOM/
Third Party Advisory https://www.debian.org/security/2020/dsa-4769
Third Party Advisory http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00008.html
FEDORA https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RJZERRBJN6E6STDCHT4JHP4MI6TKBCJE/
GENTOO https://security.gentoo.org/glsa/202011-06

Match rules

CPE URI Source package Min version Max version
cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:* xen >= None <= 4.14.0

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
xen 3.10-main 4.12.4-r0 None fixed
xen 3.12-main 4.13.4-r0 Natanael Copa <ncopa@alpinelinux.org> fixed
xen 3.11-main 4.13.4-r0 Natanael Copa <ncopa@alpinelinux.org> fixed