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Fencer Vulns
medium 5.5

CVE-2020-27784 json

A vulnerability was found in the Linux kernel, where accessing a deallocated instance in printer_ioctl() printer_ioctl() tries to access of…

published 2022-09-01 4 y ago modified 2026-06-17 4 mo ago also EUVD-2020-20286

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 14%
public exploits
0
none known

Summary

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().

Patch / fix

  • linux linux_kernel 4.4.241, 4.9.241, 4.19.154, 5.4.73, 5.8.17, 5.9.2
  • linux Debian 14, Debian 13, Debian 12 5.9.6-1

debian advisories DEBIAN-CVE-2020-27784

  • linux Ubuntu 16.04 LTS 4.4.0-197.229
  • linux Ubuntu 18.04 LTS 4.15.0-129.132
  • linux Ubuntu 20.04 LTS 5.4.0-56.62
  • linux-aws Ubuntu 16.04 LTS 4.4.0-1118.132
  • linux-aws Ubuntu 18.04 LTS 4.15.0-1091.96
  • linux-aws Ubuntu 20.04 LTS 5.4.0-1030.31
  • linux-gcp Ubuntu 16.04 LTS 4.15.0-1091.104~16.04.1
  • linux-gcp Ubuntu 20.04 LTS 5.4.0-1030.32

ubuntu advisories UBUNTU-CVE-2020-27784

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel-rt SLE Micro 5.2, SLE Micro 5.1, Real Time Module 15 SP3 +1 more 5.3.18-150300.106.1
  • kernel-syms-rt Real Time Module 15 SP3 5.3.18-150300.106.1
  • kernel-rt_debug Real Time Module 15 SP3 5.3.18-150300.106.1
  • kernel-source-rt Real Time Module 15 SP3 5.3.18-150300.106.1
  • kernel-azure SLE Module for Public Cloud 15 SP3, openSUSE Leap 15.3 5.3.18-150300.38.80.1
  • kernel-syms-azure SLE Module for Public Cloud 15 SP3, openSUSE Leap 15.3 5.3.18-150300.38.80.1
  • kernel-source-azure SLE Module for Public Cloud 15 SP3, openSUSE Leap 15.3 5.3.18-150300.38.80.1
  • kernel-syms SLES for SAP 15 SP2, SLES 15 SP2-LTSS, SLES 15 SP2-BCL +6 more 5.3.18-150200.24.129.1

suse advisories SUSE-SU-2022:3809-1SUSE-SU-2022:3609-1SUSE-SU-2022:3450-1SUSE-SU-2022:3264-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-27784 updated cvss 5.1

kernel: deallocated instance in printer_ioctl() printer_ioctl() tries to access lock_printer_io of the printer_dev instance

  • Red Hat Enterprise Linux 5 kernel Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, kernel-alt, python-perf, +9 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise MRG 2 kernel-rt, mrg-rt-release, kernel-rt-trace, kernel-rt-vanilla, kernel-rt-firmware
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.23% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • n/a kernel

Classification

Weakness
  • CWE-201 Insertion of Sensitive Information Into Sent Data
  • CWE-416 Use After Free
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.