CVE-2026-34873

An issue was discovered in Mbed TLS 3.5.0 through 4.0.0. Client impersonation can occur while resuming a TLS 1.3 session.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://mbed-tls.readthedocs.io/en/latest/security-advisories/	Vendor Advisory
https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2026-03-client-impersonation-while-resuming-tls13-session/	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:trustedfirmware:mbed_tls::::::::
	cpe:2.3:a:trustedfirmware:mbed_tls::::::::

History

No history.

Information

Published : 2026-04-01 21:17

Updated : 2026-06-17 10:39

NVD link : CVE-2026-34873

Mitre link : CVE-2026-34873

CVE.ORG link : CVE-2026-34873

JSON object : View

Products Affected

trustedfirmware

mbed_tls

CWE

CWE-287

Improper Authentication

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