CVE-2026-6679

EUVD-2026-39557
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 44.32%
Affected Products (NVD)
VendorProductVersion
wolfsslwolfssl
5.4.0 ≤
𝑥
< 5.9.1
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
wolfssl
bookworm
vulnerable
bookworm (security)
vulnerable
bullseye
postponed
sid
5.9.2-1
fixed
trixie
no-dsa
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
wolfssl
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
questing
ignored
resolute
not-affected