CVE-2023-6936: wolfssl Out-of-bounds Read — Fix

Description

In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).

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CVSS v3.1 Score

5.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Weakness Type (CWE)

CWE-125 Out-of-bounds Read

CWE-126 CWE-126

Affected Products

Vendor	Product	Versions
wolfssl	wolfssl	< 5.6.6

References

Advisories & Patches

https://github.com/wolfSSL/wolfssl/pull/6949/ https://www.wolfssl.com/docs/security-vulnerabilities/ https://github.com/wolfSSL/wolfssl/pull/6949/ https://www.wolfssl.com/docs/security-vulnerabilities/

Frequently Asked Questions

What is CVE-2023-6936? +

In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging). It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2023-6936? +

CVE-2023-6936 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-6936? +

CVE-2023-6936 affects products from wolfssl, specifically: wolfssl. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-6936? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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