Vulnerability identifier: #VU84840

Vulnerability risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-6936

CWE-ID: CWE-125

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
wolfSSL
Universal components / Libraries / Libraries used by multiple products

Vendor: wolfSSL

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition when processing a malformed ClientHello message in servers connecting over TLS 1.3 when the optional WOLFSSL_CALLBACKS has been defined. A remote attacker can trigger an out-of-bounds read error and read contents of memory on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

wolfSSL: 5.0.0 - 5.6.4

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External links
http://github.com/wolfSSL/wolfssl/releases/tag/v5.6.6-stable
http://github.com/wolfSSL/wolfssl/pull/6949

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.