Description
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.
Affected products
trustedfirmware: mbed tls
References2
- mbed-tls.readthedocs.io/en/latest/security-advisories/ Vendor Advisory
- mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-s… Vendor Advisory
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 17 · as of 12 November 2026
- CWE
- CWE-287
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.