CVE & CISA-KEV Catalog

CVE-2021-4149

MEDIUM
5.5
CVSS v3
NVD

Description

A vulnerability was found in btrfs_alloc_tree_b in fs/btrfs/extent-tree.c in the Linux kernel due to an improper lock operation in btrfs. In this flaw, a user with a local privilege may cause a denial of service (DOS) due to a deadlock problem.

How to fix

Remediation Available
linuxDebian
Fixed in:5.14.16-1CVE-2021-4149
Fixed in:5.14.16-1CVE-2021-4149
Fixed in:5.14.16-1CVE-2021-4149
linuxUbuntu
Fixed in:4.4.0-239.273USN-6014-1
Fixed in:4.15.0-184.194USN-5466-1
linux-awsUbuntu
Fixed in:4.4.0-1117.123USN-6013-1
Fixed in:4.4.0-1155.170USN-6001-1
Fixed in:4.15.0-1133.143USN-5466-1
linux-aws-hweUbuntu
Fixed in:4.15.0-1133.143~16.04.1USN-5466-1
linux-azureUbuntu
Fixed in:4.15.0-1142.156~14.04.1USN-5466-1
Fixed in:4.15.0-1142.156~16.04.1USN-5466-1
linux-azure-4.15Ubuntu
Fixed in:4.15.0-1142.156USN-5466-1
linux-gcpUbuntu
Fixed in:4.15.0-1127.142~16.04.1USN-5466-1
linux-gcp-4.15Ubuntu
Fixed in:4.15.0-1127.142USN-5466-1
linux-hweUbuntu
Fixed in:4.15.0-184.194~16.04.1USN-5466-1
linux-image-4.15.0-1098-oracleUbuntu
Fixed in:4.15.0-1098.108~16.04.1USN-5466-1
Fixed in:4.15.0-1098.108USN-5466-1
linux-image-4.15.0-1114-raspi2Ubuntu
Fixed in:4.15.0-1114.122USN-5466-1
linux-image-4.15.0-1119-kvmUbuntu
Fixed in:4.15.0-1119.123USN-5466-1
linux-image-4.15.0-1127-gcpUbuntu
Fixed in:4.15.0-1127.142~16.04.1USN-5466-1
Fixed in:4.15.0-1127.142USN-5466-1
linux-image-4.15.0-1132-snapdragonUbuntu
Fixed in:4.15.0-1132.142USN-5466-1
linux-image-4.15.0-1133-awsUbuntu
Fixed in:4.15.0-1133.143USN-5466-1
linux-image-4.15.0-1133-aws-hweUbuntu
Fixed in:4.15.0-1133.143~16.04.1USN-5466-1
linux-image-4.15.0-1142-azureUbuntu
Fixed in:4.15.0-1142.156~14.04.1USN-5466-1
Fixed in:4.15.0-1142.156~16.04.1USN-5466-1
Fixed in:4.15.0-1142.156USN-5466-1
linux-image-4.15.0-184-genericUbuntu
Fixed in:4.15.0-184.194~16.04.1USN-5466-1
Fixed in:4.15.0-184.194USN-5466-1
linux-image-4.15.0-184-generic-lpaeUbuntu
Fixed in:4.15.0-184.194USN-5466-1
linux-image-4.15.0-184-lowlatencyUbuntu
Fixed in:4.15.0-184.194~16.04.1USN-5466-1
Fixed in:4.15.0-184.194USN-5466-1
linux-image-4.4.0-1117-awsUbuntu
Fixed in:4.4.0-1117.123USN-6013-1
linux-image-4.4.0-1118-kvmUbuntu
Fixed in:4.4.0-1118.128USN-6014-1
linux-image-4.4.0-1155-awsUbuntu
Fixed in:4.4.0-1155.170USN-6001-1
linux-image-4.4.0-239-genericUbuntu
Fixed in:4.4.0-239.273~14.04.1USN-6014-1
Fixed in:4.4.0-239.273USN-6014-1
linux-image-4.4.0-239-lowlatencyUbuntu
Fixed in:4.4.0-239.273~14.04.1USN-6014-1
Fixed in:4.4.0-239.273USN-6014-1
linux-image-awsUbuntu
Fixed in:4.4.0.1117.114USN-6013-1
Fixed in:4.4.0.1155.159USN-6001-1
linux-image-aws-hweUbuntu
Fixed in:4.15.0.1133.122USN-5466-1
linux-image-aws-lts-18.04Ubuntu
Fixed in:4.15.0.1133.135USN-5466-1
linux-image-azureUbuntu
Fixed in:4.15.0.1142.113USN-5466-1
Fixed in:4.15.0.1142.131USN-5466-1
linux-image-azure-lts-18.04Ubuntu
Fixed in:4.15.0.1142.114USN-5466-1

This vulnerability affects an unusually large number of packages. The highest-confidence fixes are shown above; the full list is longer. Check the referenced advisories for complete coverage.

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorLocal
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityNone
IntegrityNone
AvailabilityHigh

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Exploit Intelligence

0.40%probability of exploitation in 30 days
33rdpercentile

Low risk: more likely to be exploited than 33% of all known CVEs.

References

Patch1
Exploit1

Related Vulnerabilities

Other CWE-667 vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2019-10072High7.573%-Fix
CVE-2002-1850High7.517%-Fix
CVE-2009-2699High7.514%-Fix
CVE-2004-0174High7.512%--
CVE-2009-4272High7.511%--
CVE-2020-24606High8.65.2%-Fix

Common questions

How do I fix CVE-2021-4149?

Published advisories record a fix for 54 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2021-4149 being actively exploited?

Not that we know of. CVE-2021-4149 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.40% is the estimated probability that it will be exploited in the next 30 days. That is higher than 33% of all scored CVEs.

How severe is CVE-2021-4149?

CVE-2021-4149 has a CVSS v3 base score of 5.5, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2021-4149 affect?

Published advisories record a fix for linux (Debian), linux (Ubuntu), linux-aws (Ubuntu), linux-aws-hwe (Ubuntu), and 50 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2021-4149
CVE-2021-4149 severity badge

Markdown

[![CVE-2021-4149](https://tridentstack.com/cve/badge/CVE-2021-4149.svg)](https://tridentstack.com/cve/CVE-2021-4149)

HTML

<a href="https://tridentstack.com/cve/CVE-2021-4149"><img src="https://tridentstack.com/cve/badge/CVE-2021-4149.svg" alt="CVE-2021-4149"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

See how it worksStart freeThis CVE lookup is free and always will be.

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.