CVE-2021-44732

Publication date 20 December 2021

Last updated 25 March 2026

Ubuntu priority

Cvss 3 Severity Score

Description

Mbed TLS before 3.0.1 has a double free in certain out-of-memory conditions, as demonstrated by an mbedtls_ssl_set_session() failure.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
mbedtls	25.10 questing	Not affected
	25.04 plucky	Not affected
	24.10 oracular	Ignored end of life, was needs-triage
	24.04 LTS noble	Not affected
	23.10 mantic	Ignored end of life, was needs-triage
	23.04 lunar	Ignored end of life, was needs-triage
	22.10 kinetic	Ignored end of life, was needs-triage
	22.04 LTS jammy	Not affected
	21.10 impish	Ignored end of life
	21.04 hirsute	Ignored end of life
	20.04 LTS focal	Fixed 2.16.4-1ubuntu2+esm1
	18.04 LTS bionic	Fixed 2.8.0-1ubuntu0.1~esm1
	16.04 LTS xenial	Vulnerable
	14.04 LTS trusty	Ignored end of standard support

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Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
mbedtls	Upstream: eb490aa

Severity score breakdown

Parameter	Value
Base score	9.8 · Critical
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

USN-8123-1
Mbed TLS vulnerabilities
25 March 2026