CVE-2019-18840 Information

Description

In wolfSSL 4.1.0 through 4.2.0c there are missing sanity checks of memory accesses in parsing ASN.1 certificate data while handshaking. Specifically there is a one-byte heap-based buffer overflow inside the DecodedCert structure in GetName in wolfcrypt/src/asn.c because the domain name location index is mishandled. Because a pointer is overwritten there is an invalid free.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Reference

https://github.com/wolfSSL/wolfssl/issues/2555

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

7.5