6.2

CVE-2025-54764: arm mbed_tls Observable Timing Discrepancy

CVSS: 6.2v3.1MediumAnalyzed
AliasesALPINE-CVE-2025-54764UBUNTU-CVE-2025-54764DEBIAN-CVE-2025-54764
Published 20-10-2025Last modified 21-10-2025
Open JSON

Vulnerability summary

CVE-2025-54764 is a medium (CVSS 6.2) Observable Timing Discrepancy vulnerability in arm mbed_tls. EPSS estimates a 0.22% chance of exploitation in the next 30 days, higher than 11.9% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.2/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.22%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference

Advisory lineage

Upstream 0 · Downstream 2 · Related 2
OPENSUSE-SU-2025:15747-1OPENSUSE-SU-2026:21144-1

Timeline

  1. 20-10-2025
    PublishedVulnerability first disclosed.
  2. 21-10-2025
    Last modifiedVulnerability information updated.

Description

Mbed TLS before 3.6.5 allows a local timing attack against certain RSA operations, and direct calls to mbedtls_mpi_mod_inv or mbedtls_mpi_gcd.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.22%

Chance of exploitation in the next 30 days

Percentile

12%

Versus all other CVEs

30-day change

+0.01 pp

From 0.21% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.22%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (mbed-tls.readthedocs.io)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Alpine1 product
  • mbedtls< 3.6.5-r0
Arm1 product
Debian1 product
  • mbedtlsAll versions (No fix recorded) | < 3.6.5-0.1~deb13u1 | < 3.6.5-0.1
Ubuntu1 product
  • mbedtlsAll versions (No fix recorded)

4 vendors · 4 products

References

10 links