CVE-2020-27675: Race Condition
First published: Thu Oct 22 2020(Updated: )
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.
Credit: cve@mitre.org
| Affected Software | Affected Version | How to fix |
|---|---|---|
| Linux kernel | <=5.9.1 | |
| Fedora | =31 | |
| Fedora | =32 | |
| Fedora | =33 | |
| Debian | =9.0 | |
| debian/linux | 5.10.223-1 5.10.234-1 6.1.123-1 6.1.128-1 6.12.12-1 6.12.17-1 |
Never miss a vulnerability like this again
Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.
Reference Links
- http://www.openwall.com/lists/oss-security/2021/01/19/3
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=073d0552ead5bfc7a3a9c01de590e924f11b5dd2
- https://github.com/torvalds/linux/commit/073d0552ead5bfc7a3a9c01de590e924f11b5dd2
- https://lists.debian.org/debian-lts-announce/2020/12/msg00015.html
- https://lists.debian.org/debian-lts-announce/2020/12/msg00027.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3ZG6TZLD23QO3PV2AN2HB625ZX47ALTT/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/6USZ4APZSBQDHGJLJMHW5JBN4QZV6SKZ/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GNF2R7FUT4IOJ2RIRGQ7X5R4F4FVVLSR/
- https://security.gentoo.org/glsa/202011-06
- https://xenbits.xen.org/xsa/advisory-331.html
- https://launchpad.net/bugs/cve/CVE-2020-27675
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3ZG6TZLD23QO3PV2AN2HB625ZX47ALTT/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6USZ4APZSBQDHGJLJMHW5JBN4QZV6SKZ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GNF2R7FUT4IOJ2RIRGQ7X5R4F4FVVLSR/
- https://security-tracker.debian.org/tracker/CVE-2020-27675
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-27675
- https://nvd.nist.gov/vuln/detail/CVE-2020-27675
- https://ubuntu.com/security/CVE-2020-27675
Frequently Asked Questions
What is the severity of CVE-2020-27675?
CVE-2020-27675 has a severe impact due to the potential for a use-after-free or NULL pointer dereference leading to system crashes.
How do I fix CVE-2020-27675?
To remediate CVE-2020-27675, upgrade your Linux kernel to version 5.10.223-1 or later, or applicable patched versions.
Which Linux versions are affected by CVE-2020-27675?
CVE-2020-27675 affects Linux kernels up to version 5.9.1 and certain Fedora and Debian releases.
What kind of issues can CVE-2020-27675 cause?
CVE-2020-27675 can lead to race conditions, causing unexpected behavior like crashes during event-handling in virtualization.
Is CVE-2020-27675 related to virtualization?
Yes, CVE-2020-27675 specifically affects the Linux kernel's handling of event channels in Xen virtualization.
- agent/type
- collector/launchpad-cve
- source/Launchpad
- agent/severity
- agent/weakness
- collector/mitre-cve
- source/MITRE
- agent/remedy
- agent/references
- agent/first-publish-date
- agent/trending
- agent/last-modified-date
- agent/source
- agent/author
- collector/usn-cve
- source/Ubuntu
- agent/description
- agent/event
- agent/softwarecombine
- agent/tags
- collector/security-tracker-debian
- source/Debian
- collector/nvd-cve
- source/NVD
- agent/software-canonical-lookup
- agent/software-canonical-lookup-request
- collector/nvd-index
- package-manager/debian
- vendor/linux
- canonical/linux kernel
- version/linux kernel/5.9.1
- vendor/fedoraproject
- canonical/fedora
- version/fedora/31
- version/fedora/32
- version/fedora/33
- vendor/debian
- canonical/debian
- version/debian/9.0