CVE-2026-5466

EUVD-2026-21291
wolfSSL's ECCSI signature verifier `wc_VerifyEccsiHash` decodes the `r` and `s` scalars from the signature blob via `mp_read_unsigned_bin` with no check that they lie in `[1, q-1]`. A crafted forged signature could verify against any message for any identity, using only publicly-known constants.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
wolfSSLCNA
7.6 HIGH
ADJACENT
LOW
NONE
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/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
< 5.9.1
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
Common Weakness Enumeration
References
https://github.com/wolfssl/wolfssl/pull/10102