CVE-2025-49600
published 2025-07-04CVE-2025-49600: 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…
PriorityP420medium4.9CVSS 3.1
AVPACHPRNUINSCCNIHAN
EPSS
0.13%
2.6th percentile
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.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | mbedtls | < mbedtls 3.6.4-1 (forky) | mbedtls 3.6.4-1 (forky) |
| mbed | mbedtls | >= 0 < 3.6.4-1 | 3.6.4-1 |
| mbed | mbedtls | >= 0 < 3.6.4-1 | 3.6.4-1 |
| mbed | mbedtls | >= 3.3.0 < 3.6.4 | 3.6.4 |
| trustedfirmware | mbed_tls | >= 3.3.0 < 3.6.4 | 3.6.4 |
CVSS provenance
nvdv3.14.9MEDIUMCVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N
osv4.9MEDIUM
vendor_debian4.9LOW
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GHSA
GHSA-r3gf-c2cf-vp8q: In MbedTLS 3
ghsa_unreviewed·2025-07-04
CVE-2025-49600 [MEDIUM] CWE-325 GHSA-r3gf-c2cf-vp8q: In MbedTLS 3
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
OSV
CVE-2025-49600: In MbedTLS 3
osv·2025-07-04·CVSS 4.9
CVE-2025-49600 [MEDIUM] CVE-2025-49600: In MbedTLS 3
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
Debian
CVE-2025-49600: mbedtls - In MbedTLS 3.3.0 before 3.6.4, mbedtls_lms_verify may accept invalid signatures ...
vendor_debian·2025·CVSS 4.9
CVE-2025-49600 [MEDIUM] CVE-2025-49600: mbedtls - In MbedTLS 3.3.0 before 3.6.4, mbedtls_lms_verify may accept invalid signatures ...
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
No detection rules found.
No public exploits indexed.
2025-07-04
Published