Vulnerability in Trustedfirmware Mbed TLS

CVE-2026-73064

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 2.9 (Low). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.001 (1.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 1st percentile — 1.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-73064: held from 0.001 to 0.001.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-73064?
CVE-2026-73064 is a low-severity vulnerability in Trustedfirmware Mbed TLS, classified under CWE-394. CVSS score: 2.9/10. Published 2026-09-24.
How severe is CVE-2026-73064?
Low severity. CVSS v3 base score is 2.9 out of 10.