CVE-2021-3669

MEDIUMNVD 5.55.5—

5.5

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.

CVSS v3: 5.5
EG Score: 5.5(medium)
EPSS: 2.9%
KEV: Not listed

Published

August 26, 2022

Last Modified

November 3, 2025

References (9)

secalert@redhathttps://access.redhat.com/security/cve/CVE-2021-3669
secalert@redhathttps://bugzilla.redhat.com/show_bug.cgi?id=1980619
secalert@redhathttps://bugzilla.redhat.com/show_bug.cgi?id=1986473
secalert@redhathttps://security-tracker.debian.org/tracker/CVE-2021-3669
af854a3a-2127-422b-91ae-364da2661108https://access.redhat.com/security/cve/CVE-2021-3669
af854a3a-2127-422b-91ae-364da2661108https://bugzilla.redhat.com/show_bug.cgi?id=1980619
af854a3a-2127-422b-91ae-364da2661108https://bugzilla.redhat.com/show_bug.cgi?id=1986473
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2024/10/msg00003.html
af854a3a-2127-422b-91ae-364da2661108https://security-tracker.debian.org/tracker/CVE-2021-3669

Patch Availability(17)

Vendor / Ecosystem	Fixed in / Patch	Released	Source
ubuntu	linux-image-azure (4.15.0.1162.128) @ trusty	2026-05-25	ubuntu
ubuntu	linux-headers-azure-edge (4.15.0.1162.146) @ xenial	2026-05-25	ubuntu
ubuntu	linux-image-azure-lts-18.04 (4.15.0.1162.130) @ bionic	2026-05-25	ubuntu
ubuntu	linux-oem-tools-host (5.4.0.146.144) @ focal	2026-05-25	ubuntu
ubuntu	linux-tools-4.15.0-208-generic (4.15.0-208.219~16.04.1) @ xenial	2026-05-25	ubuntu
ubuntu	linux-image-lowlatency (4.15.0.208.191) @ bionic	2026-05-25	ubuntu
ubuntu	linux-image-ibm-edge (5.4.0.1046.57) @ bionic	2026-05-25	ubuntu
ubuntu	linux-image-4.4.0-1117-aws (4.4.0-1117.123) @ trusty	2026-05-25	ubuntu
ubuntu	linux-tools-4.4.0-239-lowlatency (4.4.0-239.273) @ xenial	2026-05-25	ubuntu
ubuntu	linux-headers-bluefield (5.4.0.1060.55) @ focal	2026-05-25	ubuntu
ubuntu	linux-snapdragon-headers-4.15.0-1148 (4.15.0-1148.158) @ bionic	2026-05-25	ubuntu
ubuntu	linux-image-xilinx-zynqmp (5.4.0.1023.26) @ focal	2026-05-25	ubuntu
ubuntu	linux-image-gcp-lts-18.04 (4.15.0.1147.161) @ bionic	2026-05-25	ubuntu
ubuntu	linux-gcp (4.15.0.1147.137) @ xenial	2026-05-25	ubuntu
ubuntu	linux-tools-4.4.0-1155-aws (4.4.0-1155.170) @ xenial	2026-05-25	ubuntu
redhat	kernel-rt-0:4.18.0-372.9.1.rt7.166.el8	2022-05-10	redhat
redhat	kernel-0:4.18.0-372.9.1.el8	2022-05-10	redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(18)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 11× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-02 20:11 UTCepss_batch
2026-06-02 20:11 UTCepss_batch
2026-06-01 13:50 UTCepss_batch
2026-06-01 13:50 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 00:15 UTCepss_batch
2026-05-31 00:15 UTCepss_batch
2026-05-29 13:42 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-27 13:39 UTCepss_batch
2026-05-27 13:39 UTCepss_batch
2026-05-26 13:42 UTCepss_batch
2026-05-26 13:42 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-25 16:26 UTCEG score recompute
2026-05-25 16:26 UTCVendor advisory

Frequently asked(5)

What is CVE-2021-3669?

CVE-2021-3669 is a medium vulnerability published on August 26, 2022. 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.

When was CVE-2021-3669 disclosed?

CVE-2021-3669 was first published in the National Vulnerability Database on August 26, 2022, with the most recent update on November 3, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-3669 actively exploited?

CVE-2021-3669 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 2.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-3669?

CVE-2021-3669 has a CVSS v3 base score of 5.5 (NVD).

How do I remediate CVE-2021-3669?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-3669, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2021-3669

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CVE-2021-3669

Published

Last Modified

References (9)

Patch Availability(17)

Weakness Classification(2)

All Vendor Advisories

Data Freshness Timeline

Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-3669?

Same vendor

Same CWE

CVE-2021-3669

📅 Published

🔄 Last Modified

🔗 References (9)

Patch Availability(17)

Weakness Classification(2)

All Vendor Advisories

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-3669?

🔗 Related CVEs(same vendor + same CWE)

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References (9)

Frequently asked(5)

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