Vulnerability identifier: #VU66877

Vulnerability risk: Low

CVSSv3.1: 2.7 [CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: N/A

CWE-ID: CWE-763

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 perform a denial of service (DoS) attack.

The vulnerability exists due to an invalid free when handling large session tickets with TLS 1.2 and TLS 1.3 connections. A malicious server or attacker with ability to perform MitM attack (only against TLS 1.2 connection) can pass an overly large session ticket to the client and crash the application.

Note, successful exploitation of the vulnerability requires that wolfSSL is compiled with --enable-session-ticket and the client has non-empty session cache.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

wolfSSL: 5.3.0 - 5.4.0

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External links
http://github.com/wolfSSL/wolfssl/releases/tag/v5.5.0-stable

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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.