An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through…
Priority LOW 21CWE-362Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- High
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Will not fix Red Hat: no fix planned
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.
Summary
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.
Why it matters now
EPSS 0.00269 19th percentileScored 2026-11-07
Fix Will not fix Red Hat: no fix planned
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | up to 5.9.1 | Vulnerable | Linux |
| cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* | 31 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* | 32 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* | 33 | Vulnerable | Fedoraproject |
| cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Debian |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions up to 5.9.1 Vulnerable ·Linux
- cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* Versions 31 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* Versions 32 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 5 | Affected | No fix planned: Out of support scope |
Not affected: 4 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise MRG 2
Timeline
- 2026-10-02 Threatist record created from CVE-2020-27675
- 2026-10-03 Alias added: GHSA-3vrm-64pq-5964
References
Patch 3
Advisory 7
- FEDORA-2020-474d747b60
- FEDORA-2020-09e4d062fe
- FEDORA-2020-920a258c79
- GLSA-202011-06
- [debian-lts-announce] 20201210 [SECURITY] [DLA 2483-1] linux-4.19 security update
- [debian-lts-announce] 20201218 [SECURITY] [DLA 2494-1] linux security update
- [oss-security] 20210119 Xen Security Advisory 331 v3 (CVE-2020-27675) - Race condition in Linux event handler may crash dom0
Sources
- CVE-2020-27675 · CVE Program
- CVE-2020-27675 · NVD
- FIRST EPSS
- GHSA-3vrm-64pq-5964 · GitHub Advisory Database · CC BY 4.0
- CVE-2020-27675 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences