CVE-2025-27810: mbed tls — Fix

Description

Mbed TLS before 2.28.10 and 3.x before 3.6.3, in some cases of failed memory allocation or hardware errors, uses uninitialized stack memory to compose the TLS Finished message, potentially leading to authentication bypasses such as replays.

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CVSS v3.1 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-908 CWE-908

Affected Products

Vendor	Product	Versions
arm	mbed_tls	< 2.28.10
arm	mbed_tls	3.0.0 — 3.6.3

References

Advisories & Patches

https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2025-03-2/

Other References

https://github.com/Mbed-TLS/mbedtls/releases

Frequently Asked Questions

What is CVE-2025-27810? +

Mbed TLS before 2.28.10 and 3.x before 3.6.3, in some cases of failed memory allocation or hardware errors, uses uninitialized stack memory to compose the TLS Finished message, potentially leading to authentication bypasses such as replays. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2025-27810? +

CVE-2025-27810 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-27810? +

CVE-2025-27810 affects products from arm, specifically: mbed_tls. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-27810? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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