CVE-2021-3982 json
Linux distributions using CAP_SYS_NICE for gnome-shell may be exposed to a privilege escalation issue.
published 2022-04-29 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-27183
- cvss
- 5.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
Linux distributions using CAP_SYS_NICE for gnome-shell may be exposed to a privilege escalation issue. An attacker, with low privilege permissions, may take advantage of the way CAP_SYS_NICE is currently implemented and eventually load code to increase its process scheduler priority leading to possible DoS of other services running in the same machine.
Patch / fix
- gitlab.gnome.org/GNOME/mutter#2060 pull request
- gitlab.gnome.org/GNOME/gnome-shell/-/issues/2284 advisory
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-2021-3982 updated cvss 5.5
gnome-shell: Distributions using CAP_SYS_NICE in gnome-shell may be exposed to privilege escalation
-
Red Hat Enterprise Linux 7 gnome-shell, gnome-shell-browser-plugin Red Hat Enterprise Linux 8 gnome-shell Red Hat Enterprise Linux 9 gnome-shellnot 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
0.29% chance of exploitation in the next 30 days, higher than 21% 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 |
| NVD | 2.0 | 2.1 | AV:L/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- n/a gnome-shell
Classification
- Weakness
-
- CWE-273 Improper Check for Dropped Privileges
References
-
gitlab.gnome.org
/GNOME/mutter/-/merge_requests/2060
issue-tracking, patch, third-party-advisory
-
gitlab.gnome.org
/GNOME/gnome-shell/-/issues/2284
issue-tracking, patch, third-party-advisory
Sources
- CVE List CVE-2021-3982
- NVD CVE-2021-3982
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.