Vulnerability identifier: #VU84838

Vulnerability risk: Medium

CVSSv3.1: 4.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: N/A

CWE-ID: CWE-327

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 usage of weak cryptographic ciphers susceptible to a Bleichenbacher style attack. A remote attacker can decrypt a saved TLS connection and potentially forge a signature after probing with a large number of trial connections.

Note, this issue is around RSA decryption and affects static RSA cipher suites on the server side, which are not recommended to be used and are off by default.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

wolfSSL: 5.0.0 - 5.6.3

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External links
http://github.com/wolfSSL/wolfssl/releases/tag/v5.6.4-stable
http://github.com/wolfSSL/wolfssl/pull/6896

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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.