7.5

CVE-2020-36475: arm mbed_tls Incorrect Calculation of Buffer Size

CVSS: 7.5v3.1HighModified
AliasesUBUNTU-CVE-2020-36475DEBIAN-CVE-2020-36475
Published 23-08-2021Last modified 04-08-2024
Open JSON

Vulnerability summary

CVE-2020-36475 is a high (CVSS 7.5) Incorrect Calculation of Buffer Size vulnerability in arm mbed_tls. EPSS estimates a 1.92% chance of exploitation in the next 30 days, higher than 79.5% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (NVD)
EPSS score
1.92%
0%100%
Low · -0.08 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 2
DLA-2826-1DLA-3249-1

Timeline

  1. 23-08-2021
    PublishedVulnerability first disclosed.
  2. 04-08-2024
    Last modifiedVulnerability information updated.

Description

An issue was discovered in Mbed TLS before 2.25.0 (and before 2.16.9 LTS and before 2.7.18 LTS). The calculations performed by mbedtls_mpi_exp_mod are not limited; thus, supplying overly large parameters could lead to denial of service when generating Diffie-Hellman key pairs.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

1.92%

Chance of exploitation in the next 30 days

Percentile

80%

Versus all other CVEs

30-day change

-0.08 pp

From 1.99% on 19-09-2026

19-09-202619-10-2026
EPSS score
1.92%

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
Siemens2 products
Arm1 product
  • mbed_tls< 2.7.18 | ≥ 2.8.0, < 2.16.9 | ≥ 2.17.0, < 2.25.0
Ubuntu1 product
  • mbedtlsAll versions (No fix recorded)

4 vendors · 6 products

References

9 links