CVE-2026-73064 - Vulnerability Details - OpenCVE

In Mbed TLS 3.2.0 though 3.6.6 and 4.0.0 through 4.1.0, an attacker who can cause an entropy source to fail can remove or inject bytes into the start of the TLS stream. This only affects TLS 1.3 servers.

No CVSS v4.0

Attack Vector Local

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact partial

Vendors	Products
Trustedfirmware	Mbed Tls

No data.

No data.

References

Link	Providers
https://github.com/Mbed-TLS/mbedtls
https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2026-07-random-generator-fault-tls-integrity/

History

Sat, 26 Sep 2026 01:30:00 +0000

Type	Values Removed	Values Added
Title		Entropy Source Failure Enables Byte Injection in TLS 1.3 Streams

Fri, 25 Sep 2026 18:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Fri, 25 Sep 2026 06:00:00 +0000

Type	Values Removed	Values Added
First Time appeared		Trustedfirmware Trustedfirmware mbed Tls
Vendors & Products		Trustedfirmware Trustedfirmware mbed Tls

Thu, 24 Sep 2026 15:00:00 +0000

Type	Values Removed	Values Added
Description		In Mbed TLS 3.2.0 though 3.6.6 and 4.0.0 through 4.1.0, an attacker who can cause an entropy source to fail can remove or inject bytes into the start of the TLS stream. This only affects TLS 1.3 servers.
Weaknesses		CWE-394
References		https://github.com/Mbed-TLS/mbedtls https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2026-07-random-generator-fault-tls-integrity/
Metrics		cvssV3_1 `{'score': 2.9, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N'}`

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2026-09-24T14:58:38.367Z

Updated: 2026-09-24T18:00:20.196Z

Reserved: 2026-08-10T19:25:32.256Z

Link: CVE-2026-73064

Vulnrichment

Updated: 2026-09-24T18:00:17.453Z

NVD

Status : Awaiting Analysis

Published: 2026-09-24T15:17:34.273

Modified: 2026-09-24T21:04:40.340

Link: CVE-2026-73064

Redhat

No data.

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