CVE-2025-27810

Publication date 25 March 2025

Last updated 25 March 2026

Ubuntu priority

Cvss 3 Severity Score

Description

Mbed TLS before 2.28.10 and 3.x before 3.6.3, in some cases of failed memory allocation or hardware errors, uses uninitialized stack memory to compose the TLS Finished message, potentially leading to authentication bypasses such as replays.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
mbedtls	25.10 questing	Vulnerable
	25.04 plucky	Ignored end of life, was needed
	24.10 oracular	Ignored end of life, was needs-triage
	24.04 LTS noble	Fixed 2.28.8-1ubuntu0.1~esm1
	22.04 LTS jammy	Fixed 2.28.0-1ubuntu0.1~esm1
	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

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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: b5ef7da Upstream: 68014b2

Severity score breakdown

Parameter	Value
Base score	5.4 · Medium
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Changed
Confidentiality	Low
Integrity impact	Low
Availability impact	None
Vector	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N

References

Related Ubuntu Security Notices (USN)

USN-8123-1
Mbed TLS vulnerabilities
25 March 2026