CVE-2020-27784

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-09-01 · updated 2026-06-17
Weakness: CWE-201

Description

A vulnerability was found in the Linux kernel, where accessing a deallocated instance in printer_ioctl() printer_ioctl() tries to access of a printer_dev instance. However, use-after-free arises because it had been freed by gprinter_free().

Affected products

Linux kernel: from 4.1 before 4.4.241; from 4.5 before 4.9.241; from 4.10 before 4.19.154; from 4.20 before 5.4.73; from 5.5 before 5.8.17; from 5.9.0 before 5.9.2 — fixed in 4.19.154, 4.4.241, 4.9.241, 5.4.73, 5.8.17, 5.9.2

How to fix

Upgrade to a fixed version: Linux kernel 4.19.154, 4.4.241, 4.9.241, 5.4.73. Check the vendor advisory for mitigations.

References

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