CVE-2020-16150

Name: CVE-2020-16150
Creator: NVD / NIST
Published: 2020-09-02T16:15:12.363+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.36%

Last modified Jun 17, 2026

CVE-2020-16150 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. A Lucky 13 timing side channel in mbedtls_ssl_decrypt_buf in library/ssl_msg.c in Trusted Firmware Mbed TLS through 2.23.0 allows an attacker to recover secret key information. This affects CBC mode because of a computed time difference based on a padding length.. EPSS estimates a 0.36% chance of exploitation in the next 30 days.

Description

A Lucky 13 timing side channel in mbedtls_ssl_decrypt_buf in library/ssl_msg.c in Trusted Firmware Mbed TLS through 2.23.0 allows an attacker to recover secret key information. This affects CBC mode because of a computed time difference based on a padding length.

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

0.36%

27.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-203

Affected Software

Vendor	Product	Versions
Arm	Mbed Tls	< 2.7.17
Arm	Mbed Tls	>= 2.8.0, < 2.16.8
Arm	Mbed Tls	>= 2.17.0, < 2.24.0
Fedoraproject	Fedora	31
Fedoraproject	Fedora	32
Fedoraproject	Fedora	33
Debian	Debian Linux	10.0

References

https://lists.debian.org/debian-lts-announce/2022/12/msg00036.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5OSOFUD6UTGTDDSQRS62BPXDU52I6PUA/Mailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IRPBHCQKZXHVKOP5O5EWE7P76AWGUXQJ/Mailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD3NM6GD73CTFFRBKG5G2ACXGG7QQHCC/Mailing List, Third Party Advisory
https://tls.mbed.org/tech-updates/security-advisoriesVendor Advisory
https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-09-1Vendor Advisory
https://lists.debian.org/debian-lts-announce/2022/12/msg00036.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5OSOFUD6UTGTDDSQRS62BPXDU52I6PUA/Mailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IRPBHCQKZXHVKOP5O5EWE7P76AWGUXQJ/Mailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD3NM6GD73CTFFRBKG5G2ACXGG7QQHCC/Mailing List, Third Party Advisory
https://tls.mbed.org/tech-updates/security-advisoriesVendor Advisory
https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-09-1Vendor Advisory

Timeline

Published: Sep 2, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-16150?

How severe is CVE-2020-16150?

CVE-2020-16150 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.36% probability of exploitation in the next 30 days.

How do I fix CVE-2020-16150?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-16150?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST