Vulnerability · Published Feb 20, 2024 · Assigned by wolfSSL
CVE-2023-6936 Heap-buffer over-read with WOLFSSL_CALLBACKS
Medium 5.3
In plain English
A medium-severity security flaw in wolfSSL from wolfSSL. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)5.3Medium
Exploit odds (30 days)0.6%top 51.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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).
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | wolfssl | no fix listed | DEBIAN-CVE-2023-6936 |
| Debian:13 | wolfssl | 5.6.6-1.2 | DEBIAN-CVE-2023-6936 |
| Ubuntu:22.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2023-6936 |
Affected products (as reported)
Weakness: CWE-126 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N