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).

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/6949/	Issue Tracking Patch
https://www.wolfssl.com/docs/security-vulnerabilities/	Vendor Advisory
https://github.com/wolfSSL/wolfssl/pull/6949/	Issue Tracking Patch
https://www.wolfssl.com/docs/security-vulnerabilities/	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

History

26 Mar 2025, 17:15

Type	Values Removed	Values Added
CWE		CWE-126

12 Feb 2025, 17:01

Type	Values Removed	Values Added
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::
First Time		Wolfssl Wolfssl wolfssl
CWE		CWE-125
References	~~() https://github.com/wolfSSL/wolfssl/pull/6949/ -~~	() https://github.com/wolfSSL/wolfssl/pull/6949/ - Issue Tracking, Patch
References	~~() https://www.wolfssl.com/docs/security-vulnerabilities/ -~~	() https://www.wolfssl.com/docs/security-vulnerabilities/ - Vendor Advisory

21 Nov 2024, 08:44

Type	Values Removed	Values Added
References	~~() https://github.com/wolfSSL/wolfssl/pull/6949/ -~~	() https://github.com/wolfSSL/wolfssl/pull/6949/ -
References	~~() https://www.wolfssl.com/docs/security-vulnerabilities/ -~~	() https://www.wolfssl.com/docs/security-vulnerabilities/ -

20 Feb 2024, 22:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2024-02-20 22:15

Updated : 2025-03-26 17:15

NVD link : CVE-2023-6936

Mitre link : CVE-2023-6936

CVE.ORG link : CVE-2023-6936

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-125

Out-of-bounds Read

CWE-126

Buffer Over-read

{"id": "CVE-2023-6936", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "facts@wolfssl.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 1.4, "exploitabilityScore": 3.9}, {"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.1, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 3.9}]}, "published": "2024-02-20T22:15:08.197", "references": [{"url": "https://github.com/wolfSSL/wolfssl/pull/6949/", "tags": ["Issue Tracking", "Patch"], "source": "facts@wolfssl.com"}, {"url": "https://www.wolfssl.com/docs/security-vulnerabilities/", "tags": ["Vendor Advisory"], "source": "facts@wolfssl.com"}, {"url": "https://github.com/wolfSSL/wolfssl/pull/6949/", "tags": ["Issue Tracking", "Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://www.wolfssl.com/docs/security-vulnerabilities/", "tags": ["Vendor Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-125"}]}, {"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-126"}]}], "descriptions": [{"lang": "en", "value": "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).\n"}, {"lang": "es", "value": "En wolfSSL anterior a 5.6.6, si las funciones de devoluci\u00f3n de llamada est\u00e1n habilitadas (a trav\u00e9s del indicador WOLFSSL_CALLBACKS), entonces un cliente TLS malicioso o un atacante de red puede desencadenar una sobrelectura del b\u00fafer en el mont\u00f3n de 5 bytes (WOLFSSL_CALLBACKS solo est\u00e1 destinado a la depuraci\u00f3n)."}], "lastModified": "2025-03-26T17:15:23.757", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "57DCDF61-F982-41D7-83BE-DDAEC85A797A", "versionEndExcluding": "5.6.6"}], "operator": "OR"}]}], "sourceIdentifier": "facts@wolfssl.com"}