Cyber Resilience

CVE-2024-28755

Crypto Weakness in Trustedfirmware Mbed Tls 3.5.0 – 3.6.0

Published
03 April 2024
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
EPSS Score 0.0041 34th percentile
Risk Priority 51 floored blend · peak EPSS

Summary

CVE-2024-28755 is a medium-severity Inadequate Encryption Strength (CWE-326) vulnerability in Trustedfirmware Mbed Tls. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Brute Force (T1110); ranked at the 34th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-13 (Cryptographic Protection) and SC-12 (Cryptographic Key Establishment and Management) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

An issue was discovered in Mbed TLS 3.5.x before 3.6.0. When an SSL context was reset with the mbedtls_ssl_session_reset() API, the maximum TLS version to be negotiated was not restored to the configured one. An attacker was able to prevent…

more

an Mbed TLS server from establishing any TLS 1.3 connection, potentially resulting in a Denial of Service or forced version downgrade from TLS 1.3 to TLS 1.2.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1110 Brute Force Credential Access
Adversaries may use brute force techniques to gain access to accounts when passwords are unknown or when password hashes are obtained.
T1557 Adversary-in-the-Middle Credential Access
Adversaries may attempt to position themselves between two or more networked devices using an adversary-in-the-middle (AiTM) technique to support follow-on behaviors such as [Network Sniffing](https://attack.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-45159Same product: Trustedfirmware Mbed Tls
CVE-2026-25834Same product: Trustedfirmware Mbed Tls
CVE-2026-34873Same product: Trustedfirmware Mbed Tls
CVE-2026-25833Same product: Trustedfirmware Mbed Tls
CVE-2026-34874Same product: Trustedfirmware Mbed Tls
CVE-2026-34876Same product: Trustedfirmware Mbed Tls
CVE-2025-49601Same product: Trustedfirmware Mbed Tls
CVE-2024-45157Same product: Trustedfirmware Mbed Tls
CVE-2023-45199Same product: Trustedfirmware Mbed Tls
CVE-2024-30166Same product: Trustedfirmware Mbed Tls

Affected Assets

trustedfirmware
mbed tls
3.5.0 — 3.6.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 14 hardening rules · 7 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V11.4.2
  • V14.1.2
  • V14.2.4

Mitigating Controls (NIST 800-53 r5) AI

SC-13 requires selection and implementation of specific cryptographic algorithms and key lengths, directly preventing use of inadequate encryption strength.

SC-12 governs cryptographic key establishment and management, which can enforce sufficient key sizes and thereby reduce inadequate encryption strength.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.DS-01 mostly match
prevents

Strong encryption is required to protect confidentiality of data-at-rest.

PR.DS-02 mostly match
prevents

Strong encryption is required to protect confidentiality of data-in-transit.

PR.PS-01 partial match
prevents

Hardened baselines can enforce minimum cryptographic algorithm and key-length settings.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Requiring the organization to define and enforce minimum cryptographic strength prevents deployment of insufficient key lengths or weak ciphers that can be brute-forced.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 9 (1 rule)
  • V-271756 OL 9 local disk partitions must implement cryptographic mechanisms to prevent unauthorized disclosure or modification of all information that requires at rest protection. prevents CWE-326
RHEL 8 (1 rule)
  • V-230224 All RHEL 8 local disk partitions must implement cryptographic mechanisms to prevent unauthorized disclosure or modification of all information that requires at rest protection. prevents CWE-326
RHEL 9 (1 rule)
  • V-257879 RHEL 9 local disk partitions must implement cryptographic mechanisms to prevent unauthorized disclosure or modification of all information that requires at rest protection. prevents CWE-326
Windows Server 2016 (1 rule)
  • V-224843 Systems requiring data at rest protections must employ cryptographic mechanisms to prevent unauthorized disclosure and modification of the information at rest. prevents CWE-326

References