CVE-2021-3669

A flaw was found in the Linux kernel. Measuring usage of the shared memory does not scale with large shared memory segment counts which could lead to resource exhaustion and DoS.

Published: 2022-08-26 Last update: 2025-11-03 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-3669 is rated Low Risk (22.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-3669

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-11-21 0.06% 0.01% -0.05%
2 2025-11-18 0.04% 0.06% +0.02%
3 2023-03-07 — 0.04% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3669

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2021-3669

OS Trackers for CVE-2021-3669

vendor priority summary link
debian not yet assigned CVE-2021-3669 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-3669
redhat medium — https://access.redhat.com/security/cve/CVE-2021-3669
suse medium CVE-2021-3669 severity moderate: SUSE including 464 source package names (0.16.2:kmod-25-6.10.1, 0.16.2:libkmod2-25-6.10.1, …), 802 product×package rows across 113 product lines (Container caasp/v4/cilium, Container caasp/v4/etcd, … (113 product lines)): Fixed 459, Known Not Affected 183, Known Affected 160. https://www.suse.com/security/cve/CVE-2021-3669/
ubuntu low CVE-2021-3669 low priority: Ubuntu including 168 source packages (linux, linux-allwinner, …), 2116 status rows across 15 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1640, released 207, not-affected 192, ignored 77. https://ubuntu.com/security/CVE-2021-3669

Affected software / configurations for CVE-2021-3669

Vendor Product Version Raw CPE
linux linux_kernel — cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
ibm spectrum_copy_data_management >= 2.2.0.0, <= 2.2.15.0 cpe:2.3:a:ibm:spectrum_copy_data_management:*:*:*:*:*:*:*:*
ibm spectrum_protect_plus >= 10.1.0, <= 10.1.10.2 cpe:2.3:a:ibm:spectrum_protect_plus:*:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
redhat build_of_quarkus >= 2.0, < 2.7 cpe:2.3:a:redhat:build_of_quarkus:*:*:*:*:*:*:*:*
redhat developer_tools 1.0 cpe:2.3:a:redhat:developer_tools:1.0:*:*:*:*:*:*:*
redhat enterprise_linux 6.0 cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
redhat enterprise_linux 7.0 cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux_aus 8.6 cpe:2.3:o:redhat:enterprise_linux_aus:8.6:*:*:*:*:*:*:*
redhat enterprise_linux_for_ibm_z_systems 8.0 cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:8.0:*:*:*:*:*:*:*
redhat enterprise_linux_for_ibm_z_systems_eus 8.6 cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:8.6:*:*:*:*:*:*:*
redhat enterprise_linux_for_power_little_endian 8.0 cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0:*:*:*:*:*:*:*
redhat enterprise_linux_for_power_little_endian_eus 8.6 cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.6:*:*:*:*:*:*:*
redhat enterprise_linux_for_real_time 8 cpe:2.3:o:redhat:enterprise_linux_for_real_time:8:*:*:*:*:*:*:*
redhat enterprise_linux_for_real_time_for_nfv 8 cpe:2.3:o:redhat:enterprise_linux_for_real_time_for_nfv:8:*:*:*:*:*:*:*
redhat enterprise_linux_for_real_time_for_nfv_tus 8.6 cpe:2.3:o:redhat:enterprise_linux_for_real_time_for_nfv_tus:8.6:*:*:*:*:*:*:*
redhat enterprise_linux_for_real_time_tus 8.6 cpe:2.3:o:redhat:enterprise_linux_for_real_time_tus:8.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 8.6 cpe:2.3:o:redhat:enterprise_linux_server_aus:8.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions 8.6 cpe:2.3:o:redhat:enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions:8.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 8.6 cpe:2.3:o:redhat:enterprise_linux_server_tus:8.6:*:*:*:*:*:*:*
redhat codeready_linux_builder — cpe:2.3:a:redhat:codeready_linux_builder:-:*:*:*:*:*:*:*
redhat openshift_container_platform 4.6 cpe:2.3:a:redhat:openshift_container_platform:4.6:*:*:*:*:*:*:*
redhat openshift_container_platform 4.7 cpe:2.3:a:redhat:openshift_container_platform:4.7:*:*:*:*:*:*:*
redhat openshift_container_platform 4.9 cpe:2.3:a:redhat:openshift_container_platform:4.9:*:*:*:*:*:*:*
redhat virtualization_host 4.0 cpe:2.3:a:redhat:virtualization_host:4.0:*:*:*:*:*:*:*

References for CVE-2021-3669

cvelogic Threat Intelligence