5.5

CVE-2020-16150: arm mbed_tls Observable Discrepancy

CVSS: 5.5v3.1MediumModified
AliasesALPINE-CVE-2020-16150MGASA-2020-0370UBUNTU-CVE-2020-16150
Published 02-09-2020Last modified 04-08-2024
Open JSON

Vulnerability summary

CVE-2020-16150 is a medium (CVSS 5.5) Observable Discrepancy vulnerability in arm mbed_tls. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 30.9% of scored vulnerabilities.

Overall risk
22/100
0100
Low · default modelHow is this calculated?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.38%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1
DLA-3249-1

Timeline

  1. 02-09-2020
    PublishedVulnerability first disclosed.
  2. 04-08-2024
    Last modifiedVulnerability information updated.

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.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.38%

Chance of exploitation in the next 30 days

Percentile

31%

Versus all other CVEs

30-day change

0.00 pp

From 0.38% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.38%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian2 products
Alpine1 product
  • mbedtls< 2.16.8-r0
Arm1 product
  • mbed_tls< 2.7.17 | ≥ 2.8.0, < 2.16.8 | ≥ 2.17.0, < 2.24.0
Fedoraproject1 product
Mageia1 product
  • mbedtls< 2.16.8-1.mga7
Ubuntu1 product
  • mbedtlsAll versions (No fix recorded)

6 vendors · 7 products

References

14 links
Show all 14 references