CVE-2023-6936
published 2024-02-20CVE-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…
PriorityP346critical9.1CVSS 3.1
AVNACLPRNUINSUCHINAH
EPSS
0.60%
44.8th percentile
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
11 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | wolfssl | < wolfssl 5.6.6-1.2 (forky) | wolfssl 5.6.6-1.2 (forky) |
| msrc | azl3_mariadb_10.11.6-3_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| msrc | cbl2_mariadb_10.6.9-6_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| wolfssl | wolfssl | < 5.6.6 | 5.6.6 |
| wolfssl | wolfssl | <= 5.6.5 | — |
| wolfssl | wolfssl | >= 0 < 5.6.6-1.2 | 5.6.6-1.2 |
| wolfssl | wolfssl | >= 0 < 5.6.6-1.2 | 5.6.6-1.2 |
CVSS provenance
nvdv3.19.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
osv9.1CRITICAL
vendor_debian5.3MEDIUM
vendor_msrc5.3MEDIUM
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GHSA
GHSA-cwpg-8775-j56v: In wolfSSL prior to 5
ghsa_unreviewed·2024-02-21
CVE-2023-6936 [MEDIUM] CWE-125 GHSA-cwpg-8775-j56v: In wolfSSL prior to 5
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).
OSV
CVE-2023-6936: In wolfSSL prior to 5
osv·2024-02-20·CVSS 9.1
CVE-2023-6936 [CRITICAL] CVE-2023-6936: In wolfSSL prior to 5
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).
Microsoft
Heap-buffer over-read with WOLFSSL_CALLBACKS
vendor_msrc·2024-02-13·CVSS 5.3
CVE-2023-6936 [MEDIUM] CWE-126 Heap-buffer over-read with WOLFSSL_CALLBACKS
Heap-buffer over-read with WOLFSSL_CALLBACKS
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
wolfSSL: wolfSSL
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://learn.micros
Debian
CVE-2023-6936: wolfssl - In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CA...
vendor_debian·2023·CVSS 5.3
CVE-2023-6936 [MEDIUM] CVE-2023-6936: wolfssl - In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CA...
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).
Scope: local
bookworm: open
bullseye: open
forky: resolved (fixed in 5.6.6-1.2)
sid: resolved (fixed in 5.6.6-1.2)
trixie: resolved (fixed in 5.6.6-1.2)
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2024-02-20
Published