CVE-2026-4395

Heap-based buffer overflow in the KCAPI ECC code path of wc_ecc_import_x963_ex() in wolfSSL wolfcrypt allows a remote attacker to write attacker-controlled data past the bounds of the pubkey_raw buffer via a crafted oversized EC public key point. The WOLFSSL_KCAPI_ECC code path copies the input to key->pubkey_raw (132 bytes) using XMEMCPY without a bounds check, unlike the ATECC code path which includes a length validation. This can be triggered during TLS key exchange when a malicious peer sends a crafted ECPoint in ServerKeyExchange.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/9988	Patch Issue Tracking

Configurations

Configuration 1 (hide)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

History

26 Mar 2026, 18:16

Type	Values Removed	Values Added
Summary		(es) Un desbordamiento de búfer basado en montículo en la ruta de código KCAPI ECC de wc_ecc_import_x963_ex() en wolfSSL wolfcrypt permite a un atacante remoto escribir datos controlados por el atacante más allá de los límites del búfer pubkey_raw a través de un punto de clave pública EC sobredimensionado y manipulado. La ruta de código WOLFSSL_KCAPI_ECC copia la entrada a key->pubkey_raw (132 bytes) usando XMEMCPY sin una verificación de límites, a diferencia de la ruta de código ATECC que incluye una validación de longitud. Esto puede ser activado durante el intercambio de claves TLS cuando un par malicioso envía un ECPoint manipulado en ServerKeyExchange.
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::
First Time		Wolfssl Wolfssl wolfssl
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8
References	~~() https://github.com/wolfSSL/wolfssl/pull/9988 -~~	() https://github.com/wolfSSL/wolfssl/pull/9988 - Patch, Issue Tracking

19 Mar 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-19 21:17

Updated : 2026-03-26 18:16

NVD link : CVE-2026-4395

Mitre link : CVE-2026-4395

CVE.ORG link : CVE-2026-4395

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-122

Heap-based Buffer Overflow

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