- Description
- In MbedTLS 3.3.0 before 3.6.4, mbedtls_lms_verify may accept invalid signatures if hash computation fails and internal errors go unchecked, enabling LMS (Leighton-Micali Signature) forgery in a fault scenario. Specifically, unchecked return values in mbedtls_lms_verify allow an attacker (who can induce a hardware hash accelerator fault) to bypass LMS signature verification by reusing stale stack data, resulting in acceptance of an invalid signature. In mbedtls_lms_verify, the return values of the internal Merkle tree functions create_merkle_leaf_value and create_merkle_internal_value are not checked. These functions return an integer that indicates whether the call succeeded or not. If a failure occurs, the output buffer (Tc_candidate_root_node) may remain uninitialized, and the result of the signature verification is unpredictable. When the software implementation of SHA-256 is used, these functions will not fail. However, with hardware-accelerated hashing, an attacker could use fault injection against the accelerator to bypass verification.
- Source
- cve@mitre.org
- NVD status
- Analyzed
CVSS 3.1
- Type
- Secondary
- Base score
- 4.9
- Impact score
- 4
- Exploitability score
- 0.5
- Vector string
- CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N
- Severity
- MEDIUM
- cve@mitre.org
- CWE-325
- Hype score
- Not currently trending
[
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "670EA016-8FA4-4F42-A180-11243DCCD155",
"versionEndExcluding": "3.6.4",
"versionStartIncluding": "3.3.0"
}
],
"operator": "OR"
}
]
}
]