CVE-2026-5500

EUVD-2026-21293
wolfSSL's wc_PKCS7_DecodeAuthEnvelopedData() does not properly sanitize the AES-GCM authentication tag length received and has no lower bounds check. A man-in-the-middle can therefore truncate the mac field from 16 bytes to 1 byte, reducing the tag check from 2⁻¹²⁸ to 2⁻⁸.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
wolfSSLCNA
8.7 HIGH
NETWORK
LOW
NONE
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
wolfsslwolfssl
𝑥
≤ 5.9.0
CNA
Debian logo
Debian Releases
Debian Product
Codename
wolfssl
bookworm
vulnerable
bullseye
vulnerable
forky
vulnerable
sid
vulnerable
trixie
vulnerable
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
wolfssl
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
questing
needs-triage
xenial
needs-triage