CVE-2019-11873 Information

Description

wolfSSL 4.0.0 has a Buffer Overflow in DoPreSharedKeys in tls13.c when a current identity size is greater than a client identity size. An attacker sends a crafted hello client packet over the network to a TLSv1.3 wolfSSL server. The length fields of the packet: record length client hello length total extensions length PSK extension length total identity length and identity length contain their maximum value which is 2^16. The identity data field of the PSK extension of the packet contains the attack data to be stored in the undefined memory (RAM) of the server. The size of the data is about 65 kB. Possibly the attacker can perform a remote code execution attack.

CVSS Vector

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Reference

http://www.securityfocus.com/bid/108466 https://www.telekom.com/en/corporate-responsibility/data-protection-data-security/security/details/advisories-504842 https://www.telekom.com/resource/blob/572524/1c89c1cbaccdf792153063b3a10af10e/dl-190515-remote-buffer-overflow-vulnerability-wolfssl-library-data.pdf

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

9.8