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

No history.

Information

Published : 2026-03-19 18:16

Updated : 2026-06-17 10:31

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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