CVE-2020-27675

Description

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. drivers/xen/events/events_base.c allows event-channel removal during the event-handling loop (a race condition). This can cause a use-after-free or NULL pointer dereference, as demonstrated by a dom0 crash via events for an in-reconfiguration paravirtualized device, aka CID-073d0552ead5.

Category

4.7
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.09%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory kernel.org Vendor Advisory xen.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://xenbits.xen.org/xsa/advisory-331.html patch vendor advisory
https://github.com/torvalds/linux/commit/073d0552ead5bfc7a3a9c01de590e924f11b5dd2 third party advisory patch
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=073d0552ead5bfc7a3a9c01de590e924f11b5dd2 patch vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3ZG6TZLD23QO3PV2AN2HB625ZX47ALTT/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6USZ4APZSBQDHGJLJMHW5JBN4QZV6SKZ/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GNF2R7FUT4IOJ2RIRGQ7X5R4F4FVVLSR/ vendor advisory
https://security.gentoo.org/glsa/202011-06 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2020/12/msg00015.html third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2020/12/msg00027.html third party advisory mailing list
http://www.openwall.com/lists/oss-security/2021/01/19/3 third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2020-27675?
CVE-2020-27675 has been scored as a medium severity vulnerability.
How to fix CVE-2020-27675?
To fix CVE-2020-27675, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-27675 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-27675 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.