CVE-2021-20315: A locking protection bypass flaw was found in some versions of gnome-shell as shipped within CentOS Stream 8,

Q: How do I fix CVE-2021-20315?

gnome-shell: upgrade to 3.32.2; stream: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Q: Is CVE-2021-20315 being exploited?

CVE-2021-20315 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2021-20315 affect?

CVE-2021-20315 affects gnome-shell, stream. Severity is medium (CVSS 6.1). A locking protection bypass flaw was found in some versions of gnome-shell as shipped within CentOS Stream 8, when the "Application menu" or "Window list" GNOME extensions are enabled. This flaw allows a physical attacker who has access to

Q: How urgent is CVE-2021-20315?

Priority 24/100. No elevated risk signals yet.

Routine

MEDIUM 6.1UPGRADEMITIGATE

CVE-2021-20315 is a medium-severity flaw (CVSS 6.1) affecting gnome-shell, stream. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A locking protection bypass flaw was found in some versions of gnome-shell as shipped within CentOS Stream 8, when the "Application menu" or "Window list" GNOME extensions are enabled. This flaw allows a physical attacker who has access to a locked system to kill existing applications and start new ones as the locked user, even if the session is still locked.

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	6.1 (Medium)
Attack vector	Physical
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.2% (top 90%)
CISA exploited list	No
Weakness	CWE-667
Published	2022-02-18
Last modified	2026-06-17

Publisher (CNA): Red Hat, Inc. · Vendor: centos · gnome

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2022-02-18 18:15 UTCPublished CVE record published
2026-06-17 03:33 UTCUpdated Record last modified

gnome gnome-shell UPGRADE

Affected: < 3.32.2

Fixed in: 3.32.2

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy gnome-shell || rpm -q gnome-shell || gnome-shell --version

2. UPGRADE to 3.32.2 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade gnome-shell

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade gnome-shell

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

centos stream MITIGATE

Affected: 8

Fixed in: no fixed release known

Safe to downgrade to: a release before 8

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-20315?

gnome-shell: upgrade to 3.32.2; stream: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2021-20315 being exploited?

CVE-2021-20315 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-20315 affect?

CVE-2021-20315 affects gnome-shell, stream. Severity is medium (CVSS 6.1). A locking protection bypass flaw was found in some versions of gnome-shell as shipped within CentOS Stream 8, when the "Application menu" or "Window list" GNOME extensions are enabled. This flaw allows a physical attacker who has access to

How urgent is CVE-2021-20315?

Priority 24/100. No elevated risk signals yet.

Related CVEs

CVE-2023-43090 MEDIUM 5.5 UPGRADE MITIGATE A vulnerability was found in GNOME Shell
CVE-2021-3982 MEDIUM 5.5 MITIGATE Linux distributions using CAP_SYS_NICE for gnome-shell may be exposed to a privilege escalation issue
CVE-2020-17489 MEDIUM 4.3 UPGRADE MITIGATE An issue was discovered in certain configurations of GNOME gnome-shell through 3.36.4

References

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