CVE-2023-3724 TLS 1.3 client issue handling malicious server when not including a KSE and PSK extension

What is CVE-2023-3724?

CVE-2023-3724 is a critical vulnerability in Wolfssl Wolfssl, published on 17 Jul 2023.

Official description

If a TLS 1.3 client gets neither a PSK (pre shared key) extension nor a KSE (key share extension) when connecting to a malicious server, a default predictable buffer gets used for the IKM (Input Keying Material) value when generating the session master secret. Using a potentially known IKM value when generating the session master secret key compromises the key generated, allowing an eavesdropper to reconstruct it and potentially allowing access to or meddling with message contents in the session. This issue does not affect client validation of connected servers, nor expose private key information, but could result in an insecure TLS 1.3 session when not controlling both sides of the connection. wolfSSL recommends that TLS 1.3 client side users update the version of wolfSSL used.

Weakness: CWE-295, CWE-20

Which versions are affected by CVE-2023-3724?

It affects 1 product.

Products include Wolfssl Wolfssl.

How do I fix CVE-2023-3724?

Upgrade to a fixed version.

Is CVE-2023-3724 being exploited?

There is no known exploitation of CVE-2023-3724 in the wild and no public exploit code.

Other vulnerabilities in Wolfssl Wolfssl

• CVE-2024-5991 Buffer overread in domain name matching Critical 10.0
• CVE-2021-37155 Security feature bypass in n/a Critical 9.8
• CVE-2020-36177 Memory corruption in n/a Critical 9.8
• CVE-2014-2896 Memory corruption in n/a Critical 9.8
• CVE-2014-2897 Memory corruption in n/a Critical 9.8

All Wolfssl Wolfssl vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-27649, DEBIAN-CVE-2023-3724, GHSA-h4rv-393v-2f5h, JLSEC-2026-676, UBUNTU-CVE-2023-3724.