CVE-2025-49601

Description

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.

How to fix CVE-2025-49601

To remediate CVE-2025-49601, upgrade the affected package to a fixed version below.

• —upgrade to 3.6.4-r0 or later
• —upgrade to 3.6.4-1 or later

Is CVE-2025-49601 being exploited?

Low — EPSS is 0.3%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 3.6.4-r0
• from 0, < 3.6.4-1

CVSS scores

References (2)

• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2025-49601
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2025-49601