8.8
HIGH CVSS 4.0
CVE-2026-6679
DTLS 1.3 ACK serialization heap buffer overflow via integer truncation
Description

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.

INFO

Published Date :

June 25, 2026, 8:13 p.m.

Last Modified :

June 25, 2026, 8:13 p.m.

Remotely Exploit :

Yes !

Source :

wolfSSL
Affected Products

The following products are affected by CVE-2026-6679 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 HIGH 50d2cd11-d01a-48ed-9441-5bfce9d63b27
CVSS 4.0 HIGH [email protected]
Solution
Update wolfSSL to version 5.9.1 or later to fix a heap buffer overflow in DTLS 1.3 ACK serialization.
  • Update wolfSSL to version 5.9.1 or later.
  • Apply the patch for the ACK serialization fix.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-6679 vulnerability anywhere in the article.

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.