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.

Database specific

{
    "cwe_ids": [
        "CWE-190",
        "CWE-197",
        "CWE-787"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/6xxx/CVE-2026-6679.json",
    "cna_assigner": "wolfSSL"
}

References

Affected packages

Git / github.com/wolfssl/wolfssl

Affected ranges

Type

GIT

Repo

https://github.com/wolfssl/wolfssl

Events

Introduced

57aac1c50b45275c7a99eca32ad985998b292dc8

Fixed

1d363f3adceba9d1478230ede476a37b0dcdef24

Database specific

{
    "cpe": "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "5.4.0"
        },
        {
            "last_affected": "5.9.0"
        },
        {
            "fixed": "5.9.1"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "CPE_RANGE"
    ]
}

Affected versions

v5.*

v5.2.1

v5.4.0-stable

v5.5.0-stable

v5.5.1-stable

v5.5.2-stable

v5.5.3-stable

v5.5.4-stable

v5.6.0-stable

v5.6.2-stable

v5.6.3-stable

v5.6.4-stable

v5.6.6-stable

v5.7.0-stable

v5.7.2-stable

v5.7.4-stable

v5.7.6-stable

v5.8.0-stable

v5.8.2-stable

v5.8.4-stable

v5.9.0-stable

Other

wolfEntropy1

wolfEntropy2d

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-6679.json"