mbed TLS up to 3.6.3 mbedtls_lms_import_public_key out-of-bounds

Summaryinfo

A vulnerability identified as critical has been detected in mbed TLS up to 3.6.3. This issue affects the function mbedtls_lms_import_public_key. Performing a manipulation results in out-of-bounds. This vulnerability is reported as CVE-2025-49601. The attack is possible to be carried out remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in mbed TLS up to 3.6.3. This affects the function mbedtls_lms_import_public_key. The manipulation with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In MbedTLS 3.3.0 before 3.6.4, mbedtls_lms_import_public_key does not check that the input buffer is at least 4 bytes before reading a 32-bit field, allowing a possible out-of-bounds read on truncated input. Specifically, an out-of-bounds read in mbedtls_lms_import_public_key allows context-dependent attackers to trigger a crash or limited adjacent-memory disclosure by supplying a truncated LMS (Leighton-Micali Signature) public-key buffer under four bytes. An LMS public key starts with a 4-byte type indicator. The function mbedtls_lms_import_public_key reads this type indicator before validating the size of its input.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2025-49601 since 06/06/2025. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 247061 (Linux Distros Unpatched Vulnerability : CVE-2025-49601), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.6.4 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (247061) and EUVD (EUVD-2025-20079). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

• mbed TLS

Version

• 3.6.0
• 3.6.1
• 3.6.2
• 3.6.3

CPE 2.3info

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CPE 2.2info

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Be aware that VulDB is the high quality source for vulnerability data.

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