5.3

CVE-2020-36425: arm mbed_tls Improper Certificate Validation

CVSS: 5.3v3.1MediumModified
AliasesUBUNTU-CVE-2020-36425DEBIAN-CVE-2020-36425
Published 19-07-2021Last modified 04-08-2024
Open JSON

Vulnerability summary

CVE-2020-36425 is a medium (CVSS 5.3) Improper Certificate Validation vulnerability in arm mbed_tls. EPSS estimates a 0.97% chance of exploitation in the next 30 days, higher than 61.4% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
31/100
0100
Medium · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (NVD)
EPSS score
0.97%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Advisory lineage

Upstream 0 · Downstream 1
DLA-3249-1

Timeline

  1. 19-07-2021
    PublishedVulnerability first disclosed.
  2. 04-08-2024
    Last modifiedVulnerability information updated.

Description

An issue was discovered in Arm Mbed TLS before 2.24.0. It incorrectly uses a revocationDate check when deciding whether to honor certificate revocation via a CRL. In some situations, an attacker can exploit this by changing the local clock.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.97%

Chance of exploitation in the next 30 days

Percentile

61%

Versus all other CVEs

30-day change

0.00 pp

From 0.97% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.97%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Mbedtls

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Debian2 products
Arm1 product
  • mbed_tls< 2.7.17 | ≥ 2.8.0, < 2.16.8 | ≥ 2.17.0, < 2.24.0
Ubuntu1 product
  • mbedtlsAll versions (No fix recorded)

3 vendors · 4 products

References

10 links