CVE-2026-2646

A heap-buffer-overflow vulnerability exists in wolfSSL's wolfSSL_d2i_SSL_SESSION() function. When deserializing session data with SESSION_CERTS enabled, certificate and session id lengths are read from an untrusted input without bounds validation, allowing an attacker to overflow fixed-size buffers and corrupt heap memory. A maliciously crafted session would need to be loaded from an external source to trigger this vulnerability. Internal sessions were not vulnerable.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

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/9748	Issue Tracking Patch
https://github.com/wolfSSL/wolfssl/pull/9949	Issue Tracking Patch

Configurations

Configuration 1 (hide)

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

History

29 Apr 2026, 18:42

Type	Values Removed	Values Added
Summary		(es) Una vulnerabilidad de desbordamiento de búfer de montón existe en la función wolfSSL_d2i_SSL_SESSION() de wolfSSL. Al deserializar datos de sesión con SESSION_CERTS habilitado, las longitudes del certificado y del ID de sesión se leen de una entrada no confiable sin validación de límites, permitiendo a un atacante desbordar búferes de tamaño fijo y corromper la memoria del montón. Una sesión creada maliciosamente necesitaría ser cargada desde una fuente externa para activar esta vulnerabilidad. Las sesiones internas no eran vulnerables.
CWE		CWE-787
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.1
First Time		Wolfssl Wolfssl wolfssl
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::
References	~~() https://github.com/wolfSSL/wolfssl/pull/9748 -~~	() https://github.com/wolfSSL/wolfssl/pull/9748 - Issue Tracking, Patch
References	~~() https://github.com/wolfSSL/wolfssl/pull/9949 -~~	() https://github.com/wolfSSL/wolfssl/pull/9949 - Issue Tracking, Patch

19 Mar 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-19 18:16

Updated : 2026-04-29 18:42

NVD link : CVE-2026-2646

Mitre link : CVE-2026-2646

CVE.ORG link : CVE-2026-2646

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-122

Heap-based Buffer Overflow

CWE-787

Out-of-bounds Write

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