#VU84841 Cryptographic issues in wolfSSL - CVE-2023-6937

Vulnerability identifier: #VU84841

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2023-6937

CWE-ID: CWE-310

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 sensitive information.

The vulnerability exists due to wolfSSL does not check that messages in a single (D)TLS record do not span key boundaries. As a result, it is possible to combine (D)TLS messages using different keys into one (D)TLS record and force the client to accept an unencrypted flight from the server.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

wolfSSL: 5.0.0 - 5.6.4

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External links
https://github.com/wolfSSL/wolfssl/releases/tag/v5.6.6-stable
https://github.com/wolfSSL/wolfssl/pull/7029

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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.