A heap buffer overflow vulnerability exists in the DTLS 1.3 ACK serialization path of wolfSSL versions 5.9.0 and earlier. (CVE-2026-6679)
A heap buffer overflow vulnerability exists in the DTLS 1.3 ACK serialization path of wolfSSL versions 5.9.0 and earlier. The flaw is caused by an integer truncation error that leads to allocation of an undersized buffer, which is then overrun. This vulnerability was fixed in wolfSSL version 5.9.1.
AI Analysis
Technical Summary
The vulnerability in wolfSSL (CVE-2026-6679) involves a heap buffer overflow triggered during the DTLS 1.3 ACK serialization process. An integer truncation error causes the length of the ACK record-number list to be miscalculated, resulting in an undersized buffer allocation that is subsequently overrun. This can lead to memory corruption and potential impact on the confidentiality, integrity, or availability of the affected system. The issue affects wolfSSL versions up to and including 5.9.0 and was addressed in version 5.9.1.
Potential Impact
Successful exploitation of this vulnerability could lead to memory corruption due to buffer overflow, potentially allowing an attacker to cause a denial of service or execute arbitrary code. The vulnerability impacts confidentiality, integrity, and availability of the affected system. No known exploits in the wild have been reported.
Mitigation Recommendations
A fix is available in wolfSSL version 5.9.1. Users should upgrade to version 5.9.1 or later to remediate this vulnerability.
A heap buffer overflow vulnerability exists in the DTLS 1.3 ACK serialization path of wolfSSL versions 5.9.0 and earlier. (CVE-2026-6679)
Description
A heap buffer overflow vulnerability exists in the DTLS 1.3 ACK serialization path of wolfSSL versions 5.9.0 and earlier. The flaw is caused by an integer truncation error that leads to allocation of an undersized buffer, which is then overrun. This vulnerability was fixed in wolfSSL version 5.9.1.
CVSS v4.0
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in wolfSSL (CVE-2026-6679) involves a heap buffer overflow triggered during the DTLS 1.3 ACK serialization process. An integer truncation error causes the length of the ACK record-number list to be miscalculated, resulting in an undersized buffer allocation that is subsequently overrun. This can lead to memory corruption and potential impact on the confidentiality, integrity, or availability of the affected system. The issue affects wolfSSL versions up to and including 5.9.0 and was addressed in version 5.9.1.
Potential Impact
Successful exploitation of this vulnerability could lead to memory corruption due to buffer overflow, potentially allowing an attacker to cause a denial of service or execute arbitrary code. The vulnerability impacts confidentiality, integrity, and availability of the affected system. No known exploits in the wild have been reported.
Mitigation Recommendations
A fix is available in wolfSSL version 5.9.1. Users should upgrade to version 5.9.1 or later to remediate this vulnerability.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-c9q2-5c67-xg9p
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-6679"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 4.0
Threat ID: 6a3ef7e827e9c79719032d21
Added to database: 06/26/2026, 22:06:32 UTC
Last enriched: 07/18/2026, 12:56:11 UTC
Last updated: 07/31/2026, 19:23:00 UTC
Views: 66
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