CVE-2026-6679

A heap buffer overflow could occur in the DTLS 1.3 ACK serialization path before the connecting peer is authenticated. The buffer overflow was due to an integer truncation when computing the length of the ACK record-number list, causing an undersized buffer to be allocated and then overrun. This affects builds using DTLS 1.3 and wolfSSL version 5.9.0 and earlier. A fix was added to the 5.9.1 release.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/10116	Issue Tracking Patch
https://www.wolfssl.com/docs/security-vulnerabilities/	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

27 Jun 2026, 20:26

Type	Values Removed	Values Added
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::
References	~~() https://github.com/wolfSSL/wolfssl/pull/10116 -~~	() https://github.com/wolfSSL/wolfssl/pull/10116 - Issue Tracking, Patch
References	~~() https://www.wolfssl.com/docs/security-vulnerabilities/ -~~	() https://www.wolfssl.com/docs/security-vulnerabilities/ - Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
First Time		Wolfssl wolfssl Wolfssl

25 Jun 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-25 21:16

Updated : 2026-06-27 20:26

NVD link : CVE-2026-6679

Mitre link : CVE-2026-6679

CVE.ORG link : CVE-2026-6679

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-190

Integer Overflow or Wraparound

CWE-197

Numeric Truncation Error

CWE-787

Out-of-bounds Write

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