CVE-2020-27786

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-12-11 · updated 2026-06-17
Weakness: CWE-416

Description

A flaw was found in the Linux kernel’s implementation of MIDI, where an attacker with a local account and the permissions to issue ioctl commands to midi devices could trigger a use-after-free issue. A write to this specific memory while freed and before use causes the flow of execution to change and possibly allow for memory corruption or privilege escalation. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Affected products

Linux kernel: before 4.4.224; from 4.5 before 4.9.224; from 4.10 before 4.14.181; from 4.15 before 4.19.124; from 4.20 before 5.4.42; from 5.5 before 5.6.14 — fixed in 4.14.181, 4.19.124, 4.4.224, 4.9.224, 5.4.42, 5.6.14
NetApp Cloud Backup: all versions
NetApp Solidfire Baseboard Management Controller: all versions
Red Hat Enterprise Linux: 7.0, 8.0
RedHat Enterprise Mrg: 2.0
Red Hat OpenShift Container Platform 4.18: 4.4, 4.5, 4.6

How to fix

Upgrade to a fixed version: Linux kernel 4.14.181, 4.19.124, 4.4.224, 4.9.224. Check the vendor advisory for mitigations.

References

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