CVE-2026-6679
DTLS 1.3 ACK parsing overflow in wolfSSL <=5.9.0 causes heap overflow.
Is CVE-2026-6679 being exploited?
Not confirmed. CVE-2026-6679 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.51% probability of exploitation in the next 30 days.
How severe is CVE-2026-6679?
CVE-2026-6679 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-6679?
Yes. A fix has been recorded for CVE-2026-6679. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-6679 affect?
CVE-2026-6679 affects wolfSSL <= 5.9.0. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-6679?
Upgrade to wolfSSL 5.9.1+ and redeploy
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Pre-auth remote heap overflow via DTLS 1.3 ACK could crash the service or lead to code execution.
Immediate action required
- affected>= 5.4.0 and <= 5.9.0
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.