Vulnerability · Published Oct 22, 2020 · Assigned by mitre
CVE-2020-27675
Medium 4.7
In plain English
A medium-severity security flaw in the linux package (Debian). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | 5.9.6-1 | DEBIAN-CVE-2020-27675 |
| Debian:13 | linux | 5.9.6-1 | DEBIAN-CVE-2020-27675 |
| Debian:14 | linux | 5.9.6-1 | DEBIAN-CVE-2020-27675 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2020-27675 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2020-27675 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2020-27675 |
Affected products (as reported)
References
- https://xenbits.xen.org/xsa/advisory-331.html x_refsource_MISC
- https://github.com/torvalds/linux/commit/073d0552ead5bfc7a3a9c01de590e924f11b5dd2 x_refsource_MISC
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=073d0552ead5bfc7a3a9c01de590e924f11b5dd2 x_refsource_MISC
- FEDORA-2020-474d747b60 vendor-advisory, x_refsource_FEDORA
- FEDORA-2020-09e4d062fe vendor-advisory, x_refsource_FEDORA
- FEDORA-2020-920a258c79 vendor-advisory, x_refsource_FEDORA
- GLSA-202011-06 vendor-advisory, x_refsource_GENTOO
- [debian-lts-announce] 20201210 [SECURITY] [DLA 2483-1] linux-4.19 security update mailing-list, x_refsource_MLIST
- [debian-lts-announce] 20201218 [SECURITY] [DLA 2494-1] linux security update mailing-list, x_refsource_MLIST
- [oss-security] 20210119 Xen Security Advisory 331 v3 (CVE-2020-27675) - Race condition in Linux event handler may crash dom0 mailing-list, x_refsource_MLIST