CVE-2023-6936: Heap-buffer over-read with WOLFSSL_CALLBACKS
In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSLCALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSLCALLBACKS is only intended for debugging).
Affected Software
Remediation
Information
Patch Available
Event History
Frequently Asked Questions
What is the severity of CVE-2023-6936?
CVE-2023-6936 is classified as a medium severity vulnerability due to the potential buffer over-read it poses.
How do I fix CVE-2023-6936?
To fix CVE-2023-6936, upgrade to wolfSSL version 5.6.6 or later where this issue has been resolved.
What impact does CVE-2023-6936 have on my system?
CVE-2023-6936 can allow a malicious TLS client or network attacker to trigger a buffer over-read, potentially leading to information leakage.
Which versions of wolfSSL are affected by CVE-2023-6936?
CVE-2023-6936 affects wolfSSL versions prior to 5.6.6.
Is enabling WOLFSSL_CALLBACKS safe in light of CVE-2023-6936?
Enabling WOLFSSL_CALLBACKS is not safe for production environments due to the vulnerability introduced in CVE-2023-6936.