CVE-2025-52496

Publication date 4 July 2025

Last updated 25 March 2026

Ubuntu priority

Cvss 3 Severity Score

Description

Mbed TLS before 3.6.4 has a race condition in AESNI detection if certain compiler optimizations occur. An attacker may be able to extract an AES key from a multithreaded program, or perform a GCM forgery.

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: 8c67ac0 Upstream: f5db3e9

Severity score breakdown

Parameter	Value
Base score	7.8 · High
Attack vector	Local
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Changed
Confidentiality	High
Integrity impact	High
Availability impact	None
Vector	CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

References

Related Ubuntu Security Notices (USN)

USN-8123-1
Mbed TLS vulnerabilities
25 March 2026